Subject: Current Lot of ESPACER has been tested this week and is working fine.
From: James Conway <jwc@snf.stanford.edu>
Date: Fri, 31 Jul 2009 09:48:01 -0700
Fri, 31 Jul 2009 09:48:01 -0700

Greetings Ebeam and RAITH Communities:

I have had several users working with me through the course of the last 
few weeks that had reported either problems in charge compensation or 
poor contrast when imaging SOI and LTO Oxides over their target features 
during Ebeam sessions.  All of these persons were attempting overlay 
target acquisition for second layer EBL writing.  There had been 
concerns due to the fact that several weeks ago the material was left 
out and allowed to warm to room temperature over the weekend.

This week Jamal Moline, Kyeongran Yoo, and I  tested the current batch 
of ESPACER 300Z and found no problems with the solution.  We tried 3000 
rpm for 40 seconds with no post bake resulting in a sub-50 nm thin 
film.  I also worked with a Quartz substrate spinning at 5000 rpm/ 40 
seconds and a 90 second 90 degree C bake.  This film was very thin, 
maybe a bit too thin on the extreme edges,  and did not cover all mesa 
and raised target features on the substrate.  However in imaging and EBL 
writing I encountered normal contrast and only the slightest of sample 
surface charge up during high magnification imaging.

Please be frugal with this very expensive engineering material. Please 
dispense from syringes only and never pour directly from the bottle onto 
your wafer.  Currently I am using 15 drops per 100 mm wafer and obtain 
complete coverage with suitable uniformity.  Finally please make a 
personal effort to maintain this material at refrigerator temperatures 
(~5 degrees C.)

Thank You for your interest in Ebeam Technologies here at Stanford 
Nanofabrication Facility.

James Conway









Greetings Ebeam and RAITH Communities:

I have had several users working with me through the course of the last few weeks that had reported either problems in charge compensation or poor contrast when imaging SOI and LTO Oxides over their target features during Ebeam sessions.  All of these persons were attempting overlay target acquisition for second layer EBL writing.  There had been concerns due to the fact that several weeks ago the material was left out and allowed to warm to room temperature over the weekend.

This week Jamal Moline, Kyeongran Yoo, and I  tested the current batch of ESPACER 300Z and found no problems with the solution.  We tried 3000 rpm for 40 seconds with no post bake resulting in a sub-50 nm thin film.  I also worked with a Quartz substrate spinning at 5000 rpm/ 40 seconds and a 90 second 90 degree C bake.  This film was very thin, maybe a bit too thin on the extreme edges,  and did not cover all mesa and raised target features on the substrate.  However in imaging and EBL writing I encountered normal contrast and only the slightest of sample surface charge up during high magnification imaging.

Please be frugal with this very expensive engineering material. Please dispense from syringes only and never pour directly from the bottle onto your wafer.  Currently I am using 15 drops per 100 mm wafer and obtain complete coverage with suitable uniformity.  Finally please make a personal effort to maintain this material at refrigerator temperatures (~5 degrees C.)

Thank You for your interest in Ebeam Technologies here at Stanford Nanofabrication Facility.

James Conway