[Fwd: About epi poly process at stanford]

Mary Tang mtang at stanford.edu
Wed Aug 27 16:19:57 PDT 2008

Hi again --

Any thoughts?  I spoke with him again.  Basically, he says that the 
LPCVD furnace at Berkeley is labeled non-MOS, but no metals are 
allowed.  So, he's pretty confident the film would pass a TXRF.  Should 
we OK him on this?  By the way, Matt Hopcroft is a post-doc in his lab, 
so has been advising him on SNF.  Also, after speaking with him, he says 
he really does need 10-20 microns of poly.

What should we tell him?


Mary Tang wrote:
> Hi all --
> What does everyone think about this request? Would a TXRF analysis of 
> a wafer from this furnace be satisfactory? And is there an upper limit 
> on thickness for depositing epi-poly? (By the way, I will contact him 
> to inform him that TXRF may likely be required and to ask about 
> whether this thickness is actually needed for his particular 
> application and what kind of clean his wafers can undergo. But we 
> should decide in principle whether this is OK -- basically, qualifying 
> his SiC furnace for clean processing in our lab.)
> Mary
> -------- Original Message --------
> Subject:     About epi poly process at stanford
> Date:     Mon, 25 Aug 2008 16:27:56 -0700
> From:     Benjamin Cheng <kbcheng at berkeley.edu>
> To:     <mtang at stanford.edu>
> Dear Mary,
> My name is Benjamin Cheng, a graduate student working in BSAC at 
> UC-Berkeley.
> I have some questions regarding the deposition of epi-Si (ASM Epsilon 
> II Single-Wafer Epitaxial Reactor) at Stanford Nanofabrication Facility.
> I would like to know whether a 4” Silicon wafer with a thin layer of 
> poly silicon carbide (SiC) deposited (about 500nm) using LPCVD 
> (http://microlab.berkeley.edu/labmanual/chap5/5.15.html) is allowed in 
> the epi tool at Stanford for a thick layer of epi-Si (~10-20 micron). 
> Silicon carbide is well known to be very inert chemically and can 
> withstand very harsh environment. No metal is allowed in the furnace 
> tube used in depositing the SiC and so there should not be 
> contamination issue. I would greatly appreciate it if you could 
> provide me any information regarding the material compatibility of the 
> epi tool at Stanford.
> Thanks and look forward to hearing from you.
> Regards,
> Benjamin Cheng
> _____________________________________
> University of California, Berkeley
> Department of Mechanical Engineering
> Berkeley Mechanical Analysis & Design
> Office: 5109 Etcheverry Hall
> Phone: (510) 643 - 1099

Mary X. Tang, Ph.D.
Stanford Nanofabrication Facility
CIS Room 136, Mail Code 4070
Stanford, CA  94305
mtang at stanford.edu

More information about the specmat mailing list