Si/Ge PD
Contents
Overview
Gen 1: surface-normal PD
Design
Fabrication
Process flow: File:SiGePD v2 proc flow.pptx
Process follower: File:SiGePD v2 wcomments.xlsx
Results
Gen 2: waveguide PD
Design
Fabrication
Fabrication for the waveguide design is composed of two parts: pre-growth Si processing and post-growth processing. The pre-growth processing included n-implant and annealing steps. Since this had not been done by our group before, I did a brief experiment to ensure that the final doping would match the designed doping. A description of the experiment is below.
The full process flow is here: File:WGPD fullprocess.pptx
Tht process follower is here: File:WGPD Si v2.xlsx
General fabrication process development
Ge/Si hardmask etching
ICP etches using CF4 and CHF3 for SiO2 etching: File:Alternatives to SiOVert.pptx. At the time, I was using SPR220-3 as a mask, but now I use 955-0.9, which seems to come off much more cleanly.
Vertical Ge etching
ICP etches using Cl, CF4, and SF6 chemistries: File:Vertical Ge etching.pptx
N-implant verification
Phosphorous implant in Silicon: File:N-implant verification.pptx
