The Oxford PlasmaPro Deep Reactive Ion Etching (DRIE) is a system designed for etching of Si wafers.
DRIE combines isotropic silicon etching and passivation steps repeatedly to obtain anisotropic profiles. Using high density plasma source and fast gas-switching capability (Bosch process), this technique enables profile verticality, smooth sidewalls and high etching rates with high selectivity to masking materials.
The system is equipped with SF6, C4F8, N2 and O2.
Only Si is wafers are accepted in the chambers and resist should be used as a mask material.
The system is equipped with an electrostatic clamping for 6 inch wafers. Smaller substrates should be glued using resist, thermal tape of crystal bond wax.
Currently, there are 3 different optimized recipes available:
- Bosch high rate: 300um deep trenches within 280cyckles. Selectivity 1:100 to resist (AZ4562). Etch time is less than 30minutes (10um/minute)
- Bosch medium rate: 550um within 1:20hours (non linear)
- Bosch smooth sidewalls: scallops of approx. 100nm and 50nm deep (opening dependent). High aspect ratio ( >1:30)