Dear Members,

I am trying to find a cost of ownership "COO" model for LPCVD SiN Mask with
SiO2 under-layer deposition.  The mask will be used for KOH etching. On the
web I found the following:

"The total process cost of selective epitaxial growth (SEG) dielectric
isolation process as compared to LOCOS"  John C. Hughes and Gerold W.
Neudeck, School of Electrical and Computer Engineering, Purdue University,
West Lafayette, IN 47907-1285.  1997 IEEE/CPMT Int'l Electronics
Manufacturing Technology Symposium.

If I use just the information related to the SiN from the article, I get the
following:

Step            Description             Machine used                Cost per
wafer

1               Wafer Clean             Wet Station                   $0.29
2               Oxidation               Furnace                       $0.43
3               Nitridation             Furnace                       $0.43
4               Resist Mask             Noncritical stepper           $2.27
5               RIE Oxide               Dry Etcher                    $2.34
6               Resist Asher            Asher                         $0.31
7               Wafer clean             Wet Station                   $0.29

The total material cost is $6.36 per wafer for 500 wafer starts per day.
Maintenance, operator wages, clean room costs, and equipment life double
this cost.

My questions are:
1   Is this model still accurate for processing?
2   How much have the costs increased in the past ten years?
3   How do these cost change with smaller volumes?

Any help is greatly appreciated.

Mac Daily