Typically, to etch native oxide (approx 10-20 A) on silicon you can use
10% HF (etch rate approx 20-30 nm/min).
BOE has a much higher etch rate (for e.g. approx 80-90 nm/min for 6:1
BOE) and so is used to etch thick thermal oxide layers.
Hope it helps.

Mantavya

-----Original Message-----
From: mems-talk-bounces@memsnet.org
[mailto:mems-talk-bounces@memsnet.org] On Behalf Of Moshe
Sent: Thursday, November 13, 2008 4:55 AM
To: General MEMS discussion
Subject: [mems-talk] Is three is differences between BOE and HF
solution(10-48%) for etching native oxide layer?

Is three is differences between BOE and HF solution (10-48%) for etching
native oxide layer?