Re: SF6 recipe at pquest

Seongjae,

I have the old PQ log bks from 1996 to 2004. The old SiO2 etch recipe was 10H2, 15 CH4, 700w uW, 200 W bias (-102Vdc), 1.5mT, 20C. So far, I have not found any etch rate or sel numbers in the logs. Jim

----- Original Message -----
From: "Jim McVittie" <mcvittie@stanford.edu>
To: "Seongjae Cho" <felixcho2010@gmail.com>
Cc: labmembers@snf.stanford.edu
Sent: Thursday, November 29, 2012 2:50:54 PM
Subject: Re: SF6 recipe at pquest

Seongjae,

GaAs will not etch GaAs in a F based recipe if that is what you are asking. If you want to etch SiO2 over GaAs, below is a recipe from 2003 for forming micro lens. I expect Jim Kurger has an some oxide etch recipes for the PQ. Jim

Subject:
Re: PQuest Process Info Request
Date:
Thu, 3 Jul 2003 09:21:14 -0700
From:
"Michael Wiemer" <mwiemer@stanford.edu>
To:
"Jim McVittie" <mcvittie@snf.stanford.edu>
References:

> Name:_Michael Wiemer_________ Group/Company:__Miller/Harris__________
>
> Email address: __mwiemer@stanford.edu________ Date:__07-03-03_______
>
> Process name: __Mikelens___ Material to be etched:_SiO2 (quartz) and
PR__
>
> Chamber condition procedure:
>
> I usually use 15min of my etch process (described below) to condition the
chamber.
>
> Etch Process:
> Sample size__~2inX2in___, Mask Mat'l___SPR220-7___, Carrier__Silicon
(yes)
>
> Top Power__350_W, Bottom Power__75___W, Pressure___10_mT
>
> Gases and flows__CF4=32, O2=5sccms or more__________________
>
> Temperature __22C, Bias voltage__-85_V, Plasma time ___2h to 3.5h_
>
> Comment on rates, selectivity and on how well this process works:
> Works great! Transfers resist profile into the quartz wafer. Selectivity
~2.4 resist/SiO2
>

----- Original Message -----
From: "Seongjae Cho" <felixcho2010@gmail.com>
To: labmembers@snf.stanford.edu
Sent: Thursday, November 29, 2012 2:27:40 PM
Subject: SF6 recipe at pquest


Hello labmembers,

Does anyone of labmembers and staff members know a proper F-based recipe
for etching GaAs with an oxide mask at a selectivity > 4:1?
It will be really appreciated if you recommend one of recipes
of which GaAs etch rate is a value you know, with the high selectivity.

Thank you.

- Sincerely, Seongjae.