Chip is from RP2040 (Raspberry Pi Pico). More images here
Package
RP2-B0 20/34 P64M15.OQ TTT
Die
RP2 B0 2020(C) M8 R0 M7 R0 V6 B0
- Single (4861×4721, 8171000B)
- Single (4932×4798, 7180040B)
- Single (14876×14436, 38.8783MiB)
| Process step | Process | Notes |
|---|---|---|
| s1-1 | 2 min 20% hf 2 min hcl/h2o2 | minor corrosion on top metal |
| s1-2 | 2 min 20% hf 1 min hcl/h2o2 2 min barrier | |
| s1-3 | 3 min 20% hf 2 min barrier 4 min hcl/h2o2 | misc process issues causing unintended times significant top metal erosion of some sort see stringers floating around |
| s1-4 | 3 min 20% hf 2 min hcl/h2o2 4 min barrier | significant erosion into oxide looks like maybe some wax residue on die? Gentle IPA scrub w/ foam tip removed it |
| s1-5 | 2 min 20% hf 2 min hcl/h2o2 4 min barrier | much more etching lots of transistors exposed keep going at this cadence scrubbed die again to remove residue |
| s1-6 | 2 min 20% hf 2 min hcl/h2o2 4 min barrier | |
| s1-7 | 2 min 20% hf 2 min hcl/h2o2 no barrier | Getting close to done No barrier and no residue Barrier etch must be eating wax |
| s1-8 | 2 min 20% hf 2 min hcl/h2o2 no barrier | getting close to done |
| s1-9 | 2 min 20% hf 2 min hcl/h2o2 no barrier | Very small oxide left Call it good enough |