Could the polarity be applied backward?  The cathode (-) needs to be
applied to the Glass side and the anode (+) to the silicon side.
Thick oxides can cause problems too, as long as the oxide is less than
5000A 400*C at 1000V will produce a strong bond.

Hope this helps,
Loren
-----Original Message-----
From: mems-talk-bounces@memsnet.org
[mailto:mems-talk-bounces@memsnet.org] On Behalf Of ShengYi Hsiao
Sent: Thursday, March 06, 2008 12:30 AM
To: mems-talk@memsnet.org
Subject: [mems-talk] fialed in borofloat-si bonding?

Hi everybody.

Does anyone have experience in bonding borofloat glass to silicon wafer?

I am using recipe of 1000V and 400degree celcuse in vaccume environment,

however, after applying  that bonding condition for an hour, the glass
and
the

wafer still not being bonded. Only same weak connection randomly
happened,

which results the  interfering pattern. The wafers can easily be
separated.

Does anyone know the bonding condition for borofloat glass and Si?



the FAIL experiment records are :

voltage : 1000V

temperature:  400C

pressure:  9mtorr

bonding: 1 hr

bonding current: 0.02mA (form starting to the end) ....WHY?

Charge: 0~6e-2 (form starting to the end)


Any help would be greatly appreciated.

Greetings,

IAN Hsiao.