Hi All,

I have been using BOE (both 7:1 and 10:1) for a long time for oxide removal
including native oxide without any problem.   There has been a suggestion
that I should spike the BOE solution with small amount of HCl because wafer
surface after BOE treatment (without HCl spike) has haze on it (using
Surfscan Instrument).  But when wafer was treated in the BOE with HCl spike,
the haze reduces.   I have following questions:

Is this true?
If it is, what is the nature of the haze? Roughness?
How is it generated (fresh BOE solution was used) ?
Does any one (fab) in semicondor industry practice using BOE with
HCl spike or without?

Your help will be truly appreciated.

Best Regards,

Prasit Sharoenchaikit
M/A-COM, Inc
43 South Ave.,
Burlington, MA 01803
Phone: 781-564-3082