Subject: Re: Bilayer PMMA Resist Process for Liffoff
From: James Conway <jwc@snf.stanford.edu>
Date: Mon, 03 Oct 2005 16:50:28 -0700
Mon, 03 Oct 2005 16:50:28 -0700
Here is the most consistent Bilayer process we are currently using...


James Conway

Jing Kong developed a very consistent process using dual layer PMMA:
NOTE:  That this recipe utilized the chlorobenzene solvent system and 
you will have to adjust your spin speeds to the anisole spin speed (f) 
Resist thickness data or see me to check out the chlorobenzene based 
materials.  If you are interested please see me during my office hour.

Jing Kong Process No. 1:  Bi-layer PMMA Ebeam Resist for Liftoff. 
<http://snf.stanford.edu/Process/Lithography/EBResist/JKProcess1.html>

 

Revision 1.4 Dated March 1, 2003.

James W. Conway

 

This Bi-layer resist recipe utilizes both 950K PMMA and 495K PMMA.

This recipe was intended for metal liftoff and pattern has an undercut 
to aid in release.

 

 

1.      Singe Bake 150C for 30 minutes.

 

2.      Layer 1:  Spin 5% 495K PMMA in chlorobenzene   6000 rpm, 40 sec.

3.      Bake on hot plate 180C, 30 minutes.

 

4.      Layer 2:  Spin 2% 950K PMMA in chlorobenzene   5000 rpm 40 sec.

 

5.      Bake on hot plate, 180C, 30 minutes.

 

6.      Expose:  Dose: 650 - 800 uC/cm2 @ 30 KV dependent on feature 
size on H-700.

 

7.      Develop: MIBK:IPA=1:3 (volume) for 2 min
Develop time can vary from 30 sec to 2 min.  Temperature 20 - 21 C.

 

8.      Microscope Inspection:  Is pattern developed out and pattern 
cleared?

 

9.      Post Process:  Deposit Metal for liftoff, thickness as desired.

 



Li Gao wrote:

>Good morning:
>
>Does anyboday has the bi-layer PMMA recipe for metal liftoff? I found one
>one the SNF website, but is seems very old.
>
>Thanks!
>
>Best regards, Li
>
>------
>Li Gao
>Dept.of Applied Physics
>Stanford University
>Tel: (408) 927-2920
>Email: ligao@stanford.edu
>
>
>  
>


Here is the most consistent Bilayer process we are currently using...


James Conway

Jing Kong developed a very consistent process using dual layer PMMA:
NOTE:  That this recipe utilized the chlorobenzene solvent system and you will have to adjust your spin speeds to the anisole spin speed (f) Resist thickness data or see me to check out the chlorobenzene based materials.  If you are interested please see me during my office hour.

Jing Kong Process No. 1:  Bi-layer PMMA Ebeam Resist for Liftoff.

 

Revision 1.4 Dated March 1, 2003.

James W. Conway

 

This Bi-layer resist recipe utilizes both 950K PMMA and 495K PMMA.

This recipe was intended for metal liftoff and pattern has an undercut to aid in release.

 

 

1.      Singe Bake 150°C for 30 minutes.

 

2.      Layer 1:  Spin 5% 495K PMMA in chlorobenzene   6000 rpm, 40 sec.

3.      Bake on hot plate 180C, 30 minutes.

 

4.      Layer 2:  Spin 2% 950K PMMA in chlorobenzene   5000 rpm 40 sec.

 

5.      Bake on hot plate, 180C, 30 minutes.

 

6.      Expose:  Dose: 650 - 800 uC/cm2 @ 30 KV dependent on feature size on H-700.

 

7.      Develop: MIBK:IPA=1:3 (volume) for 2 min
Develop time can vary from 30 sec to 2 min.  Temperature 20 – 21 C.

 

8.      Microscope Inspection:  Is pattern developed out and pattern cleared?

 

9.      Post Process:  Deposit Metal for liftoff, thickness as desired.

 



Li Gao wrote:
Good morning:

Does anyboday has the bi-layer PMMA recipe for metal liftoff? I found one
one the SNF website, but is seems very old.

Thanks!

Best regards, Li

------
Li Gao
Dept.of Applied Physics
Stanford University
Tel: (408) 927-2920
Email: ligao@stanford.edu