DesignRules
From OptoelectronicsWiki
Design Rules
WG
- 3 um trenches for 200 um S-bends keep bending losses minimal
- Put 50 um trench around Verniers and alignment markers
VC
- 10 um x 10 um, 50 um separation
- No VC around verniers, so verviers have a chance of being exposed after substrate removal
- Using L-Edit's DRC to make sure no VCs on waveguides
Mesa
- 14 um wide
QW
- 16 um wide
Thick p metal
- Same at N metal
- 4 um wide
- Keep 11 um separation between thick P and N metal.
N Metal
- 20 um wide
Implant
- 12 um wide
- Implant after anneal to ensure the quality
Via
- Min. 6 um opening
- Open up area that is uniform at bottom
Plating
- Use SPR series positive photoresist
Square/Circular TLM patterns design rules
- Distance between adjacent pads - 4 to 30 microns in 5 or more steps.
Smaller the distance, more accurate the estimate.
- Pad width/diameter must be atleast 2x the max distance between pads.
Eg. Say if you have 6 pads with 5,8,12,15,20 micron spacing, it is recommended that the pad be > (2x20) microns wide
- Rectangular/square pads will need to be etched on the outer sides for isolation. That is not the case with circular pads.
- With circular pads, it is difficult to lift-off small rings (<5 microns)
Keep radius between 30-60 microns.
- Also, it is good to have a set of PTLMs that will be exposed to implantation step. This would be a way to check if the
implantation was effective. Resistance between pads with implantation must be hundred or kilo ohms or larger.
Document with figures to follow soon for further details.
Processing Rules
Always put a dummy/witness sample in the chamber when depositing metals and dielectrics.
- Samples can later be used for determining thicknesses.
- These samples can also be used if a given layer has to be etched on the real sample, but etch is not well characterized.