Step 43. PSG deposition and densification

 

 

 

 

Step

 

Process

Date

Operator

 

43.1

 

 

Std. clean wafers in sink6 piranha (MOS)
No HF dip!

Include PCH, Si and TiSi2 test wafer (for later exposure test)

 

11/18-19/04

Horvath

 

43.2

 
Deposit PSG in Tystar11. Target=7000A
11SDLTOA, 43 min dep. time

PSG thickness before dens.: 5500A

 

43.3

 

 

Backside etch:
- Coat wafers on SVGCOAT6, UVBAKE pr. J
- 5/1 BHF etch in sink8 until backside dewet
- Remove PR in O2 plasma (Matrix)
- Clean wafers in sink8 (MEMS) and sink6 (MOS) piranha

 

 

43.4

 

 

RTA densification in Heatpulse3:
Recipe 900RTA6.RCP
450C 30 sec
900C 10 sec

Measure PSG thickness:
PCH  5741  5380  5596  5508  5479