Step 27. Gate oxidation, Poly Si deposition

 

 

 

 

Step

 

Process

Date

Operator

 

27.1

 

 

Target: 80A gate oxide + 2500A Poly Si

TCA clean Tystar1 (TCA clean was performed 3 times before the oxidation due to problems with Tystar10)

 

10/07/04

Horvath

 

27.2

 
- Remove PR in Matrix std. 1.5 min O2 ash.
- Clean wafers in piranha in sink8 (MEMS). Include NCH, PCH test wafers.
- Clean wafers in piranha in sink6 (MOS). Include NCH, PCH, Tox, Tpoly1, Tpoly2 test wafers. Test wafers are p-type prime, 40-60 Ohm-cm
- 10/1 HF dip wafers until NCH, PCH dewet (~1 min) in sink6. (R~15Mohm)

 

27.3

 

 

Gate oxidation in Tystar1:

Recipe 1THIN-OX
850C, 30 min oxidation
900C, 30 min N2 annealing

Include NCH, PCH, Tox, Tpoly1, Tpoly2 plus 3 test dummies

Note: ALMACK step25 in furnace process unless the pre-oxidation furnace temp. is 450C

 





27.4
  
  Poly Si deposition in Tystar10:

  Immediately after gate oxidation.
  Recipe 10SUPLYA (undoped poly)
  28 min. deposition time

   Include Tpoly1, Tpoly2 plus 3 test dummies

 

27.5

 

 

Measurements:

  • Gate oxide thickness on Tox:
Sopra: 80.37A (center)
Rudolph: 79, 78, 77, 79, 77A (T, C, F, L, R)
  • SCA measurement results on Tox:
Nsc = 6.39-6.45 E 14
Qox = 8.76-8.95 E 10
Dit = 1.02 E 10 -> below resolution
Ts= 301-309
  • Sheet resistance on NCH, PCH after oxide strip:
NCH: 686-700 Ohm/sq
PCH: 730-750 Ohm/sq
  • Poly thickness:


 T
 C
 F
 L
 R
Tpoly
 2593
 2657
 2826
 2725
 2620
w#1
 2627
 2710
 2846
 2785
 2665
w#5
 2568
 2652
 2746
 2699
 2587
w#10
 2399
 2428
 2478
 2451
 2399