From mtang at stanford.edu  Mon May  2 15:38:24 2011
From: mtang at stanford.edu (Mary Tang)
Date: Mon, 02 May 2011 15:38:24 -0700
Subject: Metalica and STS
In-Reply-To: <AFD07D1BD0F1AF458A18EEDEFCAE717D01232C4ED387@EXCHCLUSTER1-02.win.slac.stanford.edu>
References: <4C65CB39.4060906@stanford.edu> <AFD07D1BD0F1AF458A18EEDEFCAE717D01232C4ED387@EXCHCLUSTER1-02.win.slac.stanford.edu>
Message-ID: <4DBF3260.2090001@stanford.edu>

Hi Jiquan --

I'm forwarding your note to the SpecMat group as well as Jeannie.  By 
the way, do you have your own target?  I trust that you should hear from 
one of us in the next day or so.

Mary

On 5/2/2011 12:11 PM, Guo, Jiquan wrote:
> Hi, Jeannie and Mary:
>
> I have couple of questions about materials in Metalica and STS.
>
> I plan to sputter Nb/Sn on a two inch sapphire or Nb sample, then coat SiO2 or SiN in STS. I have checked the vapor pressure for Nb and Sn, and they are lower than In, so it should be OK for Metalica. But I'm not sure if Sn is OK for STS.
>
> I was using Kapton tape to fix two inch samples on 4 inch wafers when using Metalica, but separating them is a big hassle. Is it possible that I make some two inch carriers from metals like Aluminum or stainless steel, with a 1.98 inch hole in the center?
>
> Thanks a lot.
>
> Jiquan


-- 
Mary X. Tang, Ph.D.
Stanford Nanofabrication Facility
Paul G. Allen Room 136, Mail Code 4070
Stanford, CA  94305
(650)723-9980
mtang at stanford.edu
http://snf.stanford.edu



From mtang at stanford.edu  Tue May  3 15:06:20 2011
From: mtang at stanford.edu (Mary Tang)
Date: Tue, 03 May 2011 15:06:20 -0700
Subject: Fwd: Re: Doping service
Message-ID: <4DC07C5C.4010201@stanford.edu>

Hi all --

Can this be done at SNF?  I spoke with him on the phone, but did not 
realize it was one atm. of H2.  Any other options you can think of?

M

-------- Original Message --------
Subject: 	Re: Doping service
Date: 	Tue, 3 May 2011 14:58:50 -0700 (PDT)
From: 	Champ Phuthong <phuthong at stanford.edu>
To: 	mtang at snf.stanford.edu



Hi Mary,

Attached is the paper and here is the excerpt for the process
"Then-Ti02crystalswere mechanically polished to A. /10 optical quality and then doped in a hydrogen furnace. The hydrogen pressure was kept at 1 atm and the doping controlled by varying the exposure time to temperatures ranging from 400-600 ?C. The samples became deep blue at high dopings and virtually opaque at carrier concentrations above 10^19 carriers/cm3"

I hope SNF is able to do it. Also, can you give me the contact person for the polishing?
Regard,
Champ

----- Original Message -----
From: "Champ Phuthong"<phuthong at stanford.edu>
To: mtang at snf.stanford.edu
Sent: Friday, April 29, 2011 2:41:43 PM
Subject: Re: Doping service

Dear Mary,

My name is Champ Phuthong, an MSE student. I would like to have TiO2 rutile substrate doped in a hydrogen furnace.  The hydrogen pressure was kept at 1 atm at about 500 celcius to get the concentration at 10^19 carriers/cm^3. Referred to you from Maureen, I wonder if the SNF staff can do that for me or I have to join SNF in order to do it myself. If I use the doping service, how much am I going to be charged?

Regards,
Champ

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From mtang at stanford.edu  Thu May  5 16:41:37 2011
From: mtang at stanford.edu (Mary Tang)
Date: Thu, 05 May 2011 16:41:37 -0700
Subject: Fwd: Re: New Material ErAs:GaAs
Message-ID: <4DC335B1.1050407@stanford.edu>

Hi all --

I answered Mike and he went and got some info.  I'll forward shortly.

Mary

-------- Original Message --------
Subject: 	Re: New Material ErAs:GaAs
Date: 	Wed, 4 May 2011 18:21:13 -0700
From: 	Michael Kozina <mkozina at stanford.edu>
To: 	Mary Tang <mtang at stanford.edu>



Mary:

I'm still waiting on my collaborators for explicit information about 
ErAs:GaAs in answer to your questions.  And yes, there is a lift-off 
involved that I forgot to put in the process.  As soon as I have 
something from someone in the group who made this material, I'll pass it 
on to you.

Thanks,
Mike Kozina

On Thu, Apr 28, 2011 at 6:07 PM, Mary Tang <mtang at stanford.edu 
<mailto:mtang at stanford.edu>> wrote:

    Hi Mike --

    On the face of it, this should be OK because there's no high temp
    processing or etching.  However, I've got a few questions:

    1.  Granted, the bulk of the material is GaAs which is OK, but I'm
    not familiar with ErAs.  Will the temperatures for vacuum prime and
    LOL bake be compatible with this film?  I'm assuming the film is
    chemically compatible with developer (<2% TMAH)?  And acetone (is
    there a lift-off we're missing)?  I think that as long as this film
    is stable under these conditions and not incompatible with the
    chemicals it will come into contact with, it should be OK.

    2.  Pieces are teeny -- smaller, I think, than the smallest chuck.
      Please make sure to check with the litho folks about proper
    procedures for handling small pieces on the headway (maybe even the
    karlsuss too.)

    3.  Baking of LOL does not need to be in the BlueM oven and is most
    often done on a hot plate.


    Mahnaz might have some some additional inputs about the litho.  But
    I would suggest a quick confirmation from your collaborator about
    the chemical compatibility with the chemicals to be used to satisfy
    my paranoia.  (Not that the minute quantity you have would pose a
    problem, but if we open the door to ErAs, it would be good to have
    additional info.)  By the way, a google search turned up American
    Elements which supplies bulk ErAs -- any chance of an MSDS from them?

    So, a quick note or email to us from your collaborator or
    knowledgeable person/chemist in that group confirming chemical
    compatibility - then, I'd say you're good.

    Cheers --

    Mary


    On 4/27/2011 2:45 PM, Mike Kozina wrote:

        Hello,

        I would like to bring a new material, ErAs:GaAs, into the SNF
        and am seeking your approval.

        Personal Information:

        Name: Michael Kozina
        Coral login: mkozina
        Phone Number: 650-926-5382 <tel:650-926-5382> (work),
        209-662-1094 <tel:209-662-1094> (cell)
        Email: mkozina at stanford.edu <mailto:mkozina at stanford.edu>
        PI: David Reis, Department of Applied Physics/PULSE (SLAC)

        Chemical:

        This is GaAs with a thin (1.8micron) layer on top of ErAs
        islands interspersed in GaAs. I do not have an MSDS for this
        material (it is a new material developed by a collaborator). I
        am not sure of the specific Storage Group Identifier that would
        be most appropriate, but it seems that what works for GaAs
        should also work for this. Moreover, the same hazards that apply
        to GaAs apply to this material.

        The material was made by Art Gossard's group in the Materials
        Science Department at UC Santa Barbara.
        Website: http://engineering.ucsb.edu/faculty/profile/169
        Phone: 805 893-2686 <tel:805%20893-2686>

        Reason for Request: We are studying various properties of this
        specific material, and we want to be able to put a certain
        pattern of gold on it. We don't have the facilities ourselves,
        and want to use the nanofab lab. There is no new procedure
        involved here per se--we're just going to use photolithography
        and sputtering to partially cover 4x4mm pieces of ErAs:GaAs.

        Process Flow (note I don't plan on using equipment that are
        solely "clean"--ie everything will be at the gold-contaminated
        level):

        1. Prime with HMDS in YES oven.
        2. Spin on LOL with the headway.
        3. Bake on LOL in Blue-M oven.
        4. Spin on photoresist with headway.
        5. Bake on photoresist.
        6. Expose using Karl Suss
        7. Develop at wbmiscres.
        8. Metallize with metallica.

        Amount and Form:

        I will bring in at most 1/4 of a 2" wafer of material. It is in
        solid form, divided into 4x4mm pieces.

        Storage:

        I don't plan to store this material at the SNF.

        Disposal:

        I will dispose of any sort of waste as I would for GaAs (using
        the appropriate As waste bins).

        Attached are three publications that detail how this material is
        made.

        Thanks,
        Mike Kozina




    -- 
    Mary X. Tang, Ph.D.
    Stanford Nanofabrication Facility
    Paul G. Allen Room 136, Mail Code 4070
    Stanford, CA  94305
    (650)723-9980 <tel:%28650%29723-9980>
    mtang at stanford.edu <mailto:mtang at stanford.edu>
    http://snf.stanford.edu



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From mtang at stanford.edu  Thu May  5 16:42:43 2011
From: mtang at stanford.edu (Mary Tang)
Date: Thu, 05 May 2011 16:42:43 -0700
Subject: Fwd: Fwd: Processing stability questions about ErAs
Message-ID: <4DC335F3.5070105@stanford.edu>

Hi Mike --

Thanks for following up -- you're good to go.

Mary

-------- Original Message --------
Subject: 	Fwd: Processing stability questions about ErAs
Date: 	Thu, 5 May 2011 16:01:03 -0700
From: 	Michael Kozina <mkozina at stanford.edu>
To: 	Mary Tang <mtang at stanford.edu>



Mary:

I've forwarded you an email from the collaborator who grew our ErAs:GaAs 
material.  It looks like everything is compatible.  I looked but 
couldn't find an MSDS for ErAs from American Elements (or elsewhere online).

Thanks,
Mike Kozina

---------- Forwarded message ----------
From: *Bjorn Vermeersch* <bvermeer at soe.ucsc.edu 
<mailto:bvermeer at soe.ucsc.edu>>
Date: Thu, May 5, 2011 at 12:50 PM
Subject: Fwd: Processing stability questions about ErAs
To: Michael Kozina <mkozina at stanford.edu <mailto:mkozina at stanford.edu>>


Hi Mike,

Please see below for Je-Hyeong's comments, it looks good. He has done
the processing of my switch samples and has worked for several years
at the nanofab at UC Santa Barbara so he has a lot of clean room
experience.

Best,
Bjorn

---------- Forwarded message ----------
From: Je-Hyeong Bahk <jhbahk at soe.ucsc.edu <mailto:jhbahk at soe.ucsc.edu>>
Date: 5 May 2011 12:25
Subject: RE: Processing stability questions about ErAs
To: Bjorn Vermeersch <bvermeer at soe.ucsc.edu <mailto:bvermeer at soe.ucsc.edu>>


Bjorn,

The ErAs:GaAs should be compatible with TMAH and Aceton. They should also be
stable below ~450 degC as their growth temperature is 490 degC.

Thanks,
Je-Hyeong

-----Original Message-----
From: Bjorn Vermeersch [mailto:bvermeer at soe.ucsc.edu 
<mailto:bvermeer at soe.ucsc.edu>]
Sent: Thursday, May 05, 2011 10:56 AM
To: Je-Hyeong Bahk
Cc: Michael Kozina
Subject: Processing stability questions about ErAs

Hi Je-Hyeong,

Mike and Vinayak at Stanford, who do the x-ray experiments on our
photoconductive material, like to get their nanofab facility to
approve use of ErAs:GaAs material so they could deposit the metal
contacts. They need to provide some information about the
chemical/temperature stability of ErAs during processing.

Any chance you could help them with the short questions below?

Thanks,
Bjorn


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From kenney at slac.stanford.edu  Mon May  9 22:23:26 2011
From: kenney at slac.stanford.edu (Kenney, Christopher J.)
Date: Mon, 9 May 2011 22:23:26 -0700
Subject: Tungsten request
Message-ID: <4D3AEE67-87CD-4F83-877C-4E6728A56E82@slac.stanford.edu>

Dear Specmat,

I would like to etch some tungsten foil in one of the STSETCH machines.

This is high-purity 4N material from EpiMetals.

The foils are 50 microns thick and would be mounted on a standard silicon wafer.

Standard WBMETAL cleans would be used prior to placing the tungsten in the STSETCH.

Only a small fraction the area would be exposed and etched. I may have a student work on this over the
summer, if it is approved.

Thank you,

Chris

From jimkruger at yahoo.com  Mon May 23 09:58:17 2011
From: jimkruger at yahoo.com (jim kruger)
Date: Mon, 23 May 2011 09:58:17 -0700 (PDT)
Subject: Return of Methane channel to N2
Message-ID: <653748.92322.qm@web38902.mail.mud.yahoo.com>


SpecMat request  5-23-11



I have been running N2 plasma surface
treatments in STS, results look promising.



For these tests, I need staff help from
Jim Haydon to switch the pneumatic logic to get N2 to run as a
process gas.  An extra channel, formerly used for Methane for SiC
deposition, exists.  The spare channel is no longer connected to the
Methane line and could easily be reconnected to UHP N2.



The channel is already labeled as N2 in
the STS software.



I believe the Methane has not been used
in years and would not be missed.



I request the change back to UHP N2.  I
do expect ongoing use for N2 plasma surface treatments.



Jim Kruger



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From jperez at snf.stanford.edu  Mon May 23 10:22:38 2011
From: jperez at snf.stanford.edu (Jeannie Perez)
Date: Mon, 23 May 2011 10:22:38 -0700
Subject: Return of Methane channel to N2
In-Reply-To: <653748.92322.qm@web38902.mail.mud.yahoo.com>
References: <653748.92322.qm@web38902.mail.mud.yahoo.com>
Message-ID: <4DDA97DE.7010309@snf.stanford.edu>

I have had complaints that the chamber has lots of particles when Jim 
Kruger has done his N2 processing. I recommend some type of Cleaning 
procedure from him when done.
Jeannie

On 5/23/2011 9:58 AM, jim kruger wrote:
>
> SpecMat request 5-23-11
>
>
> I have been running N2 plasma surface treatments in STS, results look 
> promising.
>
>
> For these tests, I need staff help from Jim Haydon to switch the 
> pneumatic logic to get N2 to run as a process gas. An extra channel, 
> formerly used for Methane for SiC deposition, exists. The spare 
> channel is no longer connected to the Methane line and could easily be 
> reconnected to UHP N2.
>
>
> The channel is already labeled as N2 in the STS software.
>
>
> I believe the Methane has not been used in years and would not be missed.
>
>
> I request the change back to UHP N2. I do expect ongoing use for N2 
> plasma surface treatments.
>
>
> Jim Kruger
>
>

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From kenney at slac.stanford.edu  Tue May 24 12:00:01 2011
From: kenney at slac.stanford.edu (Kenney, Christopher J.)
Date: Tue, 24 May 2011 12:00:01 -0700
Subject: Fwd: Tungsten request
References: <4D3AEE67-87CD-4F83-877C-4E6728A56E82@slac.stanford.edu>
Message-ID: <CA4FD84E-D94A-4C65-B6A2-158E9B5CA890@slac.stanford.edu>



Begin forwarded message:

From: "Kenney, Christopher J." <kenney at slac.stanford.edu<mailto:kenney at slac.stanford.edu>>
Date: May 9, 2011 10:23:26 PM PDT
To: "specmat at snf.stanford.edu<mailto:specmat at snf.stanford.edu>" <specmat at snf.stanford.edu<mailto:specmat at snf.stanford.edu>>
Subject: Tungsten request

Dear Specmat,

I would like to etch some tungsten foil in one of the STSETCH machines.

This is high-purity 4N material from EpiMetals.

The foils are 50 microns thick and would be mounted on a standard silicon wafer.

Standard WBMETAL cleans would be used prior to placing the tungsten in the STSETCH.

Only a small fraction the area would be exposed and etched. I may have a student work on this over the
summer, if it is approved.

Thank you,

Chris



From mtang at stanford.edu  Tue May 24 14:17:03 2011
From: mtang at stanford.edu (Mary Tang)
Date: Tue, 24 May 2011 14:17:03 -0700
Subject: Fwd: Tungsten request
In-Reply-To: <CA4FD84E-D94A-4C65-B6A2-158E9B5CA890@slac.stanford.edu>
References: <4D3AEE67-87CD-4F83-877C-4E6728A56E82@slac.stanford.edu> <CA4FD84E-D94A-4C65-B6A2-158E9B5CA890@slac.stanford.edu>
Message-ID: <4DDC204F.4080504@stanford.edu>

Hi Chris --

I take it that you plan to use SF6 to etch W?  According to the website, 
stsetch is semiclean, but metals are not supposed to be exposed to the 
plasma.  It may have been approved on a case-by-case basis previously 
(anyone on SpecMat know for certain?)

Aside from this, there are a few other questions:

1.  How is the W foil mounted on the wafer?
2.  What is the mask material?
3.  How deep is the etch and what is the stopping material, if applicable?
4.  Why the stsetch as opposed to p5000etch ChA?

Anyone else have other questions?

Mary

On 5/24/2011 12:00 PM, Kenney, Christopher J. wrote:
>
> Begin forwarded message:
>
> From: "Kenney, Christopher J."<kenney at slac.stanford.edu<mailto:kenney at slac.stanford.edu>>
> Date: May 9, 2011 10:23:26 PM PDT
> To: "specmat at snf.stanford.edu<mailto:specmat at snf.stanford.edu>"<specmat at snf.stanford.edu<mailto:specmat at snf.stanford.edu>>
> Subject: Tungsten request
>
> Dear Specmat,
>
> I would like to etch some tungsten foil in one of the STSETCH machines.
>
> This is high-purity 4N material from EpiMetals.
>
> The foils are 50 microns thick and would be mounted on a standard silicon wafer.
>
> Standard WBMETAL cleans would be used prior to placing the tungsten in the STSETCH.
>
> Only a small fraction the area would be exposed and etched. I may have a student work on this over the
> summer, if it is approved.
>
> Thank you,
>
> Chris
>


-- 
Mary X. Tang, Ph.D.
Stanford Nanofabrication Facility
Paul G. Allen Room 136, Mail Code 4070
Stanford, CA  94305
(650)723-9980
mtang at stanford.edu
http://snf.stanford.edu



From kenney at slac.stanford.edu  Wed May 25 09:33:41 2011
From: kenney at slac.stanford.edu (Kenney, Christopher J.)
Date: Wed, 25 May 2011 09:33:41 -0700
Subject: Tungsten request
In-Reply-To: <4DDC204F.4080504@stanford.edu>
References: <4D3AEE67-87CD-4F83-877C-4E6728A56E82@slac.stanford.edu>
 <CA4FD84E-D94A-4C65-B6A2-158E9B5CA890@slac.stanford.edu>
 <4DDC204F.4080504@stanford.edu>
Message-ID: <F1A1A396-21D0-460B-8908-A2AA248C382E@slac.stanford.edu>

Hi Mary,

Yes, etching with SF6.

I think the rule intends that aluminum shouldn't be exposed. The W
reaction products should be volatile unlike the aluminum, which is largely
sputtered off and redeposited all over the chamber and eventually on other
people's wafers. Of course the holder/ring is aluminum ...

So the W chemistry should be closer to silicon's than aluminum's in the context of
contaminating the chamber. 

We can do SF6 and O2 cleans following any etch.

1) W foil would be held on a silicon wafer using resist bonding or polyimide tape
2) photoresist would be the mask material covering about 95 percent of the wafer area
3) At most the etch would go all the way through the foil, which is 50 microns. It would stop
on PR or silicon.
4) For anisotropic etching we could even use H2O2. For high-aspect ratio, deep features I think we'd need
to use STSETCH just like for silicon.

Thanks,

Chris


 
On May 24, 2011, at 2:17 PM, Mary Tang wrote:

> Hi Chris --
> 
> I take it that you plan to use SF6 to etch W?  According to the website, 
> stsetch is semiclean, but metals are not supposed to be exposed to the 
> plasma.  It may have been approved on a case-by-case basis previously 
> (anyone on SpecMat know for certain?)
> 
> Aside from this, there are a few other questions:
> 
> 1.  How is the W foil mounted on the wafer?
> 2.  What is the mask material?
> 3.  How deep is the etch and what is the stopping material, if applicable?
> 4.  Why the stsetch as opposed to p5000etch ChA?
> 
> Anyone else have other questions?
> 
> Mary
> 
> On 5/24/2011 12:00 PM, Kenney, Christopher J. wrote:
>> 
>> Begin forwarded message:
>> 
>> From: "Kenney, Christopher J."<kenney at slac.stanford.edu<mailto:kenney at slac.stanford.edu>>
>> Date: May 9, 2011 10:23:26 PM PDT
>> To: "specmat at snf.stanford.edu<mailto:specmat at snf.stanford.edu>"<specmat at snf.stanford.edu<mailto:specmat at snf.stanford.edu>>
>> Subject: Tungsten request
>> 
>> Dear Specmat,
>> 
>> I would like to etch some tungsten foil in one of the STSETCH machines.
>> 
>> This is high-purity 4N material from EpiMetals.
>> 
>> The foils are 50 microns thick and would be mounted on a standard silicon wafer.
>> 
>> Standard WBMETAL cleans would be used prior to placing the tungsten in the STSETCH.
>> 
>> Only a small fraction the area would be exposed and etched. I may have a student work on this over the
>> summer, if it is approved.
>> 
>> Thank you,
>> 
>> Chris
>> 
> 
> 
> -- 
> Mary X. Tang, Ph.D.
> Stanford Nanofabrication Facility
> Paul G. Allen Room 136, Mail Code 4070
> Stanford, CA  94305
> (650)723-9980
> mtang at stanford.edu
> http://snf.stanford.edu
> 



From kenney at slac.stanford.edu  Wed May 25 10:56:30 2011
From: kenney at slac.stanford.edu (Kenney, Christopher J.)
Date: Wed, 25 May 2011 10:56:30 -0700
Subject: Tungsten request
In-Reply-To: <2124813747.98100.1306345227757.JavaMail.root@zm06.stanford.edu>
References: <2124813747.98100.1306345227757.JavaMail.root@zm06.stanford.edu>
Message-ID: <F9504532-7CB4-405C-AB62-61FBEAA00BB1@slac.stanford.edu>

Hi Jim,

Super thanks for providing this treasure trove of information.

Chris

On May 25, 2011, at 10:40 AM, James P McVittie wrote:

> Chris,
> 
> For W etching background, I am attaching the AMAT W etch process report and the W recipe for chamber A (see below).  I am also attaching 2 papers on W etching based on SF6 plus an additive (N2 and H2). I will scan my old notebook pages on W etching in the drytek using SF6/F115.  Let me know if you find any papers using a modified Bosch process for W.  
> 
> Jim  
> 
> 
> P5000 W etch in chamber A recipe:
> 1) You need SF6 chemistry to etch through TiW. Put this step behind your Al
> OE step.
> 50SF6/20BCl3/30mT/40G/200W/8Torr Backside He.   Most customers use time to
> control the step. But you can use endpoint also if you like.
> You need to start new endpoint recipe during TiW step.   F wavelength 7280A
> should be used during TiW step. Try the following endpoint program as the
> starting
> point. Wavelength 3960/AGC level 50/AGC time 10/initial dead time 20/window
> height -0.20/window time 2/Number of windows in 2/Derivative time
> 0.0/Display Start Level 60/ Display Gain  10/Magnetic Field 2.1/Number of
> Field period to Average 10
> 2) You should be able to etch TiO2 layer as long as that layer is not too
> thick.
> 
> ----- Original Message -----
> From: "Christopher J. Kenney" <kenney at slac.stanford.edu>
> To: "Mary Tang" <mtang at stanford.edu>
> Cc: specmat at snf.stanford.edu, "Ed Myers" <edmyers at stanford.edu>
> Sent: Wednesday, May 25, 2011 9:33:41 AM
> Subject: Re: Tungsten request
> 
> Hi Mary,
> 
> Yes, etching with SF6.
> 
> I think the rule intends that aluminum shouldn't be exposed. The W
> reaction products should be volatile unlike the aluminum, which is largely
> sputtered off and redeposited all over the chamber and eventually on other
> people's wafers. Of course the holder/ring is aluminum ...
> 
> So the W chemistry should be closer to silicon's than aluminum's in the context of
> contaminating the chamber. 
> 
> We can do SF6 and O2 cleans following any etch.
> 
> 1) W foil would be held on a silicon wafer using resist bonding or polyimide tape
> 2) photoresist would be the mask material covering about 95 percent of the wafer area
> 3) At most the etch would go all the way through the foil, which is 50 microns. It would stop
> on PR or silicon.
> 4) For anisotropic etching we could even use H2O2. For high-aspect ratio, deep features I think we'd need
> to use STSETCH just like for silicon.
> 
> Thanks,
> 
> Chris
> 
> 
> 
> On May 24, 2011, at 2:17 PM, Mary Tang wrote:
> 
>> Hi Chris --
>> 
>> I take it that you plan to use SF6 to etch W?  According to the website, 
>> stsetch is semiclean, but metals are not supposed to be exposed to the 
>> plasma.  It may have been approved on a case-by-case basis previously 
>> (anyone on SpecMat know for certain?)
>> 
>> Aside from this, there are a few other questions:
>> 
>> 1.  How is the W foil mounted on the wafer?
>> 2.  What is the mask material?
>> 3.  How deep is the etch and what is the stopping material, if applicable?
>> 4.  Why the stsetch as opposed to p5000etch ChA?
>> 
>> Anyone else have other questions?
>> 
>> Mary
>> 
>> On 5/24/2011 12:00 PM, Kenney, Christopher J. wrote:
>>> 
>>> Begin forwarded message:
>>> 
>>> From: "Kenney, Christopher J."<kenney at slac.stanford.edu<mailto:kenney at slac.stanford.edu>>
>>> Date: May 9, 2011 10:23:26 PM PDT
>>> To: "specmat at snf.stanford.edu<mailto:specmat at snf.stanford.edu>"<specmat at snf.stanford.edu<mailto:specmat at snf.stanford.edu>>
>>> Subject: Tungsten request
>>> 
>>> Dear Specmat,
>>> 
>>> I would like to etch some tungsten foil in one of the STSETCH machines.
>>> 
>>> This is high-purity 4N material from EpiMetals.
>>> 
>>> The foils are 50 microns thick and would be mounted on a standard silicon wafer.
>>> 
>>> Standard WBMETAL cleans would be used prior to placing the tungsten in the STSETCH.
>>> 
>>> Only a small fraction the area would be exposed and etched. I may have a student work on this over the
>>> summer, if it is approved.
>>> 
>>> Thank you,
>>> 
>>> Chris
>>> 
>> 
>> 
>> -- 
>> Mary X. Tang, Ph.D.
>> Stanford Nanofabrication Facility
>> Paul G. Allen Room 136, Mail Code 4070
>> Stanford, CA  94305
>> (650)723-9980
>> mtang at stanford.edu
>> http://snf.stanford.edu
>> 
> 
> <w-Etch-SF6-H2-2mT85V.pdf><W-TiNEtchingOverHiK-2002.pdf><WEB Process Release 1.01pdf.pdf>



From mahnaz at stanford.edu  Tue May 31 11:14:19 2011
From: mahnaz at stanford.edu (Mahnaz Mansourpour)
Date: Tue, 31 May 2011 11:14:19 -0700
Subject: Laurell
In-Reply-To: <BANLkTikQ4CwCaQxxUpzCZSRQ_5OBKdA90A@mail.gmail.com>
References: <4DE515BF.1020603@stanford.edu>	<BANLkTikyO0UodnmBswthVk=x9eGuscnHoA@mail.gmail.com>	<4DE529C6.9010108@stanford.edu> <BANLkTikQ4CwCaQxxUpzCZSRQ_5OBKdA90A@mail.gmail.com>
Message-ID: <4DE52FFB.9020605@stanford.edu>

Hi J,

It has been some times we are wondering who/ what is leaving this white 
gooey stuff in the system.
So often we come in and we end up cleaning it and not knowing what it is ?
I have seen this on the headway chuck actually James showed it to me a 
week a go and I had no idea what it was?

I do not recall  any info about this through specmat  but i can be wrong 
and if any one on the list has any please forward it to me.
Even if we had it okay I would have asked not to be spun on the this 
tool, and the procedure next to the tool specifically says what is 
allowed ONLY.
As you can see from  the report  another lab member had to clean up the 
mess ...


Found the bowl contaminated with what appears to be white crystalline material that is not soluble in acetone or IPA.  Scrapped most out with a dry wipe, then wiped with a water wet wipe, followed by acetone wipe and dry.  I cannot imagine what this material might have been but it is somewhat similar in appearance to the ammonium fluoride crystals often found around the BOE tanks at WBNONMETAL.  But surely no one would be spinning BOE in the laurel spinner.  WTF?

mahnaz



On 5/31/2011 10:49 AM, J Provine wrote:
> mahnaz,
> not specific specmat approval for this test.  i understood suspended 
> powders to be allowable.
>
> the powder was suspended in water.
> j
>
> On Tue, May 31, 2011 at 10:47 AM, Mahnaz Mansourpour 
> <mahnaz at stanford.edu <mailto:mahnaz at stanford.edu>> wrote:
>
>     Hi J,
>
>     Have we okay this?
>     Do you have the specmat approval for it?
>
>     What material the powder was dispersed  in?
>
>     mahnaz
>
>
>     On 5/31/2011 9:48 AM, J Provine wrote:
>>     hi mahnaz,
>>     i helped some students from ee17n run 1 wafer with a suspended
>>     aluminate powder.  the powder was not thoroughly held by the
>>     suspension as we found out as soon as we spun the first wafer.  i
>>     tried to clean everything up thoroughly and scrubbed until i
>>     didn't see anything anymore.
>>     j
>>
>>     On Tue, May 31, 2011 at 9:22 AM, Mahnaz Mansourpour
>>     <mahnaz at stanford.edu <mailto:mahnaz at stanford.edu>> wrote:
>>
>>
>>         Hi J,
>>
>>         What material did you run on Laurell on Thursday 26th?
>>
>>         mahnaz
>>
>>
>
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From jprovine at stanford.edu  Tue May 31 12:38:56 2011
From: jprovine at stanford.edu (J Provine)
Date: Tue, 31 May 2011 12:38:56 -0700
Subject: Laurell
In-Reply-To: <4DE52FFB.9020605@stanford.edu>
References: <4DE515BF.1020603@stanford.edu>
	<BANLkTikyO0UodnmBswthVk=x9eGuscnHoA@mail.gmail.com>
	<4DE529C6.9010108@stanford.edu>
	<BANLkTikQ4CwCaQxxUpzCZSRQ_5OBKdA90A@mail.gmail.com>
	<4DE52FFB.9020605@stanford.edu>
Message-ID: <BANLkTimkifuZ+D=LJbMjLb4qkvmi9X+QmA@mail.gmail.com>

well any other instance would not be related since it was only that one
wafer that i ran.
so whatever happened with headway or other times should be investigated
independently.
j

On Tue, May 31, 2011 at 11:14 AM, Mahnaz Mansourpour <mahnaz at stanford.edu>wrote:

>  Hi J,
>
> It has been some times we are wondering who/ what is leaving this white
> gooey stuff in the system.
> So often we come in and we end up cleaning it and not knowing what it is ?
> I have seen this on the headway chuck actually James showed it to me a week
> a go and I had no idea what it was?
>
> I do not recall  any info about this through specmat  but i can be wrong
> and if any one on the list has any please forward it to me.
> Even if we had it okay I would have asked not to be spun on the this tool,
> and the procedure next to the tool specifically says what is allowed ONLY.
> As you can see from  the report  another lab member had to clean up the
> mess ...
>
>
> Found the bowl contaminated with what appears to be white crystalline material that is not soluble in acetone or IPA.  Scrapped most out with a dry wipe, then wiped with a water wet wipe, followed by acetone wipe and dry.  I cannot imagine what this material might have been but it is somewhat similar in appearance to the ammonium fluoride crystals often found around the BOE tanks at WBNONMETAL.  But surely no one would be spinning BOE in the laurel spinner.  WTF?
>
> mahnaz
>
>
>
> On 5/31/2011 10:49 AM, J Provine wrote:
>
> mahnaz,
> not specific specmat approval for this test.  i understood suspended
> powders to be allowable.
>
>  the powder was suspended in water.
> j
>
> On Tue, May 31, 2011 at 10:47 AM, Mahnaz Mansourpour <mahnaz at stanford.edu>wrote:
>
>>  Hi J,
>>
>> Have we okay this?
>> Do you have the specmat approval for it?
>>
>> What material the powder was dispersed  in?
>>
>> mahnaz
>>
>>
>> On 5/31/2011 9:48 AM, J Provine wrote:
>>
>> hi mahnaz,
>> i helped some students from ee17n run 1 wafer with a suspended aluminate
>> powder.  the powder was not thoroughly held by the suspension as we found
>> out as soon as we spun the first wafer.  i tried to clean everything up
>> thoroughly and scrubbed until i didn't see anything anymore.
>> j
>>
>> On Tue, May 31, 2011 at 9:22 AM, Mahnaz Mansourpour <mahnaz at stanford.edu>wrote:
>>
>>>
>>> Hi J,
>>>
>>> What material did you run on Laurell on Thursday 26th?
>>>
>>> mahnaz
>>>
>>
>>
>
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From mahnaz at stanford.edu  Tue May 31 12:58:26 2011
From: mahnaz at stanford.edu (Mahnaz Mansourpour)
Date: Tue, 31 May 2011 12:58:26 -0700
Subject: Laurell
In-Reply-To: <BANLkTimkifuZ+D=LJbMjLb4qkvmi9X+QmA@mail.gmail.com>
References: <4DE515BF.1020603@stanford.edu>	<BANLkTikyO0UodnmBswthVk=x9eGuscnHoA@mail.gmail.com>	<4DE529C6.9010108@stanford.edu>	<BANLkTikQ4CwCaQxxUpzCZSRQ_5OBKdA90A@mail.gmail.com>	<4DE52FFB.9020605@stanford.edu> <BANLkTimkifuZ+D=LJbMjLb4qkvmi9X+QmA@mail.gmail.com>
Message-ID: <4DE54862.4010900@stanford.edu>

J,

That is true but Now that I think about it, how did you get the chemical 
in the lab?
You should have  had the yellow labels and log the chemical in the 
binder in my office, non of these
were done?
Any explanation?

mahnaz

On 5/31/2011 12:38 PM, J Provine wrote:
> well any other instance would not be related since it was only that 
> one wafer that i ran.
> so whatever happened with headway or other times should be 
> investigated independently.
> j
>
> On Tue, May 31, 2011 at 11:14 AM, Mahnaz Mansourpour 
> <mahnaz at stanford.edu <mailto:mahnaz at stanford.edu>> wrote:
>
>     Hi J,
>
>     It has been some times we are wondering who/ what is leaving this
>     white gooey stuff in the system.
>     So often we come in and we end up cleaning it and not knowing what
>     it is ?
>     I have seen this on the headway chuck actually James showed it to
>     me a week a go and I had no idea what it was?
>
>     I do not recall  any info about this through specmat  but i can be
>     wrong and if any one on the list has any please forward it to me.
>     Even if we had it okay I would have asked not to be spun on the
>     this tool, and the procedure next to the tool specifically says
>     what is allowed ONLY.
>     As you can see from  the report  another lab member had to clean
>     up the mess ...
>
>
>     Found the bowl contaminated with what appears to be white crystalline material that is not soluble in acetone or IPA.  Scrapped most out with a dry wipe, then wiped with a water wet wipe, followed by acetone wipe and dry.  I cannot imagine what this material might have been but it is somewhat similar in appearance to the ammonium fluoride crystals often found around the BOE tanks at WBNONMETAL.  But surely no one would be spinning BOE in the laurel spinner.  WTF?
>
>     mahnaz
>
>
>
>     On 5/31/2011 10:49 AM, J Provine wrote:
>>     mahnaz,
>>     not specific specmat approval for this test.  i understood
>>     suspended powders to be allowable.
>>
>>     the powder was suspended in water.
>>     j
>>
>>     On Tue, May 31, 2011 at 10:47 AM, Mahnaz Mansourpour
>>     <mahnaz at stanford.edu <mailto:mahnaz at stanford.edu>> wrote:
>>
>>         Hi J,
>>
>>         Have we okay this?
>>         Do you have the specmat approval for it?
>>
>>         What material the powder was dispersed  in?
>>
>>         mahnaz
>>
>>
>>         On 5/31/2011 9:48 AM, J Provine wrote:
>>>         hi mahnaz,
>>>         i helped some students from ee17n run 1 wafer with a
>>>         suspended aluminate powder.  the powder was not thoroughly
>>>         held by the suspension as we found out as soon as we spun
>>>         the first wafer.  i tried to clean everything up thoroughly
>>>         and scrubbed until i didn't see anything anymore.
>>>         j
>>>
>>>         On Tue, May 31, 2011 at 9:22 AM, Mahnaz Mansourpour
>>>         <mahnaz at stanford.edu <mailto:mahnaz at stanford.edu>> wrote:
>>>
>>>
>>>             Hi J,
>>>
>>>             What material did you run on Laurell on Thursday 26th?
>>>
>>>             mahnaz
>>>
>>>
>>
>
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From jprovine at stanford.edu  Tue May 31 13:04:16 2011
From: jprovine at stanford.edu (J Provine)
Date: Tue, 31 May 2011 13:04:16 -0700
Subject: Laurell
In-Reply-To: <4DE54862.4010900@stanford.edu>
References: <4DE515BF.1020603@stanford.edu>
	<BANLkTikyO0UodnmBswthVk=x9eGuscnHoA@mail.gmail.com>
	<4DE529C6.9010108@stanford.edu>
	<BANLkTikQ4CwCaQxxUpzCZSRQ_5OBKdA90A@mail.gmail.com>
	<4DE52FFB.9020605@stanford.edu>
	<BANLkTimkifuZ+D=LJbMjLb4qkvmi9X+QmA@mail.gmail.com>
	<4DE54862.4010900@stanford.edu>
Message-ID: <BANLkTi=U_AYwmo6DpU3g+FKKy7iT7R+jqw@mail.gmail.com>

I made a mistake.
J

On Tuesday, May 31, 2011, Mahnaz Mansourpour <mahnaz at stanford.edu> wrote:
>
>
>
>
>
>
>     J,
>
>     That is true but Now that I think about it, how did you get the
>     chemical in the lab?
>     You should have? had the yellow labels and log the chemical in the
>     binder in my office, non of these
>     were done?
>     Any explanation?
>
>     mahnaz
>
>     On 5/31/2011 12:38 PM, J Provine wrote:
>     well any other instance would not be related since it
>       was only that one wafer that i ran.
>       so whatever happened with headway or other times should be
>         investigated independently.
>       j
>
>
>           On Tue, May 31, 2011 at 11:14 AM, Mahnaz Mansourpour <mahnaz at stanford.edu>
>           wrote:
>
>              Hi J,
>
>               It has been some times we are wondering who/ what is
>               leaving this white gooey stuff in the system.
>               So often we come in and we end up cleaning it and not
>               knowing what it is ?
>               I have seen this on the headway chuck actually James
>               showed it to me a week a go and I had no idea what it was?
>
>               I do not recall? any info about this through specmat? but
>               i can be wrong and if any one on the list has any please
>               forward it to me.
>               Even if we had it okay I would have asked not to be spun
>               on the this tool, and the procedure next to the tool
>               specifically says what is allowed ONLY.
>               As you can see from? the report? another lab member had to
>               clean up the mess ...
>
>
>               Found the bowl contaminated with what appears to be white crystalline material that is not soluble in acetone or IPA.  Scrapped most out with a dry wipe, then wiped with a water wet wipe, followed by acetone wipe and dry.  I cannot imagine what this material might have been but it is somewhat similar in appearance to the ammonium fluoride crystals often found around the BOE tanks at WBNONMETAL.  But surely no one would be spinning BOE in the laurel spinner.  WTF?
>
> mahnaz
>
>
>
>                   On 5/31/2011 10:49 AM, J Provine wrote:
>                   mahnaz,
>                     not specific specmat approval for this test. ?i
>                       understood suspended powders to be allowable.
>
>
>                     the powder was suspended in water.
>                     j
>
>                       On Tue, May 31, 2011 at
>                         10:47 AM, Mahnaz Mansourpour <mahnaz at stanford.edu>
>                         wrote:
>
>                            Hi J,
>
>                             Have we okay this?
>                             Do you have the specmat approval for it?
>
>                             What material the powder was dispersed? in?
>
>                               mahnaz
>
>
>
>                                 On 5/31/2011 9:48 AM, J Provine wrote:
>                                 hi mahnaz,
>                                   i helped some students from ee17n
>                                     run 1 wafer with a suspended
>                                     aluminate powder. ?the powder was
>                                     not thoroughly held by the
>                                     suspension as we found out as soon
>                                     as we spun the first wafer. ?i tried
>                                     to clean everything up thoroughly
>                                     and scrubbed until i didn't see
>                                     anything anymore.
>                                   j
>
>                                     On Tue, May
>                                       31, 2011 at 9:22 AM, Mahnaz
>                                       Mansourpour <mahnaz at stanford.edu>
>                                       wrote:
>
>
>