From ntayebi at stanford.edu  Mon Jun  7 16:57:42 2010
From: ntayebi at stanford.edu (Noureddine Tayebi)
Date: Mon, 7 Jun 2010 16:57:42 -0700 (PDT)
Subject: released time from 2 to 6 PM tomorrow (tuesday)
Message-ID: <1999949041.386013.1275955062398.JavaMail.root@zm02.stanford.edu>



From mihirt at stanford.edu  Thu Jun 17 15:21:58 2010
From: mihirt at stanford.edu (Mihir Tendulkar)
Date: Thu, 17 Jun 2010 15:21:58 -0700 (PDT)
Subject: Raising the horns -- and then removing them (Pt etch question)
Message-ID: <932605387.905848.1276813318078.JavaMail.root@zm01.stanford.edu>

Hi MRC users, 

I've discovered that when I sputter etch Pt in the MRC, using the recipe listed in the logbook, I get substantial redeposition at the corners of my features, resulting in "horns" that short out my devices. 

I am going to try depositing at a higher pressure to get a more isotropic etch and hopefully get rid of these features. Has anyone found a recipe that works well for this purpose? Sidewall sharpness is not critical for me. 

Thanks in advance. 

-- 
Mihir Tendulkar
Applied Physics PhD Candidate
Nishi Group, Stanford University


From jimkruger at yahoo.com  Thu Jun 17 17:00:35 2010
From: jimkruger at yahoo.com (jim kruger)
Date: Thu, 17 Jun 2010 17:00:35 -0700 (PDT)
Subject: Raising the horns -- and then removing them (Pt etch question)
In-Reply-To: <932605387.905848.1276813318078.JavaMail.root@zm01.stanford.edu>
Message-ID: <97996.75384.qm@web38906.mail.mud.yahoo.com>

You did not say how thick is the Pt.? Stop on what material?

2 approaches: 
?I etch 300 A Pt with a resist mask (about 1.6 um), P=12 mTorr, 80 watts, then clean away sidewalls by acetone? soak for 7 or 10 minutes, then gentle acetone swab with a foam-tip swab from Litho, keep the wafer wet with acetone, flush with acetone, then IPA and blow dry.

2nd approach if it fits your process:? use a thin hard mask of Cr or Ti or PECVD SiO2.? The sidewall deposition is limited to the thickness of the hard mask.

Higher sputtering pressure just makes it worse.

jim

--- On Thu, 6/17/10, Mihir Tendulkar <mihirt at stanford.edu> wrote:

From: Mihir Tendulkar <mihirt at stanford.edu>
Subject: Raising the horns -- and then removing them (Pt etch question)
To: "mrc" <mrc at snf.stanford.edu>
Date: Thursday, June 17, 2010, 3:21 PM

Hi MRC users, 

I've discovered that when I sputter etch Pt in the MRC, using the recipe listed in the logbook, I get substantial redeposition at the corners of my features, resulting in "horns" that short out my devices. 

I am going to try depositing at a higher pressure to get a more isotropic etch and hopefully get rid of these features. Has anyone found a recipe that works well for this purpose? Sidewall sharpness is not critical for me. 

Thanks in advance. 

-- 
Mihir Tendulkar
Applied Physics PhD Candidate
Nishi Group, Stanford University



      
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://snf.stanford.edu/pipermail/mrc/attachments/20100617/65d68dc6/attachment.html>