cha


NanoLab cha manual

cha is a multi-material e-beam evaporator. It holds three wafers (or chips) at once in a rotating planetary mount. We often use it to deposit chromium and gold. This is the standard evaporator for the NanoLab. A good backup is ebeam1, which has extremely similar capabilities (save cha's fancy but optional automatic deposition rate controller).

picture of cha tool

Process Notes

Date Person Data
22 Oct 2020 Daniel Tool power supply is replaced and is more powerful; processes should be recalibrated.
21 May 2021 Daniel Cr evaporates at about 25mA (45% LOW beam power). Au evaporates at about 40mA (60% LOW beam power).
12 Jul 2021 Daniel Ti evaporates at about 65mA (36% MID beam power). Pt evaporates at about 170mA (51% MID beam power). Both are extremely bright and heat the wafer significantly.
12 Jul 2021 Daniel 11nm Ti + 70nm Pt on standard 2um MiR701 makes photoresist start to flake/reticulate; more causes cracking. Liftoff works but barely.