Microgear Transmission Process Sequence Diagram Presented By Christian

Microgear Transmission Process Sequence Diagram Presented By: Christian Daco James Ford Michael Layman Huey Lee Allan Siu

Starting with a silicon substrate… Silicon Substrate

1. LPCVD 2 m layer silicon dioxide (Si. O 2) Si. H 4 + O 2 Si. O 2 + H 2 @ Temp 400 – 500 C Silicon Dioxide Silicon Substrate

2. LPCVD 1 m polysilicon layer. Si. H 4 Si + 2 H 2 @ Temp = 600 -650 C Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

3. Coat photoresist. Photoresist Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

4. Expose and develop photoresist. Photoresist Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

5. Etch polysilicon layer by plasma etching in Cl 2 to expose silicon dioxide layer. Photoresist Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

6. Strip photoresist in H 2 SO 4/H 2 O 2 Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

7. Wet etch Si. O 2 layer with HF Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

8. Deposit sacrificial Si. O 2 layer conformally with tetraethylorthosilicate (TEOS) Silicon Dioxide Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

9. Deposit 1 m polysilicon layer with LPCVD. Polysilicon Layer #2 Silicon Dioxide Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

10. Apply photoresist and pattern gear shape. Photoresist Polysilicon Layer #2 Silicon Dioxide Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

(Zoom out view to see gear formation) Photoresist Polysilicon Layer #2 Silicon Dioxide Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

11. Plasma dry etch in Cl 2 to create gear shape Polysilicon Layer #2 Photoresist Silicon Dioxide Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

(Zoom in) 12. Strip photoresist in H 2 SO 4/H 2 O 2 Polysilicon Layer #2 Silicon Dioxide Polysilicon Layer #1 Silicon Dioxide Silicon Substrate

13. Wet etch Si. O 2 layer with HF to release gear. Polysilicon Layer #2 Silicon Dioxide Polysilicon Layer #1 Silicon Dioxide Silicon Substrate