Deep Trenches
Deep Reactive Ion Etching - DRIE
DRIE is a high aspect ratio, deep trench silicon etching process (Bosch process). The principle of the deep trench silicon etching process is an alternating fluorine based etching and passivation of the structures. This results in sidewall profiles of 90°±1° with aspect ratios of up to 40:1. Masking layers can be made of photo resist or silicon oxide.
There are currently two Alcatel 601E systems and one STS/ICP system installed, which brings the total number of production tools to five.
Main Benefits of DRIE
- etch rate of up to 10 µm/min
- aspect ratio up to 40:1
- selectivity to positive resist > 75:1
- selectivity to silicon oxide >150:1
- etch depth capability 10 to 675 µm (through wafer etching)
- sidewall profile 90°±1°
- feature size 1 to >500 µm
Alcatel AMS200 & 601E
Alcatel's deep plasma etch technology is designed to deliver superior process performance and maximum process flexibility to meet the needs of a broad range of deep silicon etch applications.
- Applications in MEMS and microsystems fabrication include: high aspect ratios, etch depths of as great as 675 µm, etching through-the-wafer, etching into a buried cavity in the wafer, or etching onto buried oxide.
- Applications in deep trench isolation include: etching bulk silicon or silicon-on-insulator (SOI) structures with vertical or positive profiles with very high etch rates for high throughput.