Power MEMS Development
Monthly status rept. 1-30 Nov 2009
SRI INTERNATIONAL MENLO PARK CA PHYSICAL SCIENCES DIV
Pagination or Media Count:
SHORT LOOP EXPERIMENTS During this period we completed one short loop experiment to verify the use of chromium Cr as a hard mask for silicon dioxide SiO2 wet etching. This Cr hard mask was used during the fabrication of the Indent layer in the process flow. For this experiment, we deposited 3-micrometers of SiO2 on the wafer and then sputtered a layer of Cr. We patterned and etched the Cr, creating the hard mask, and then etched the SiO2 using a 61 buffered oxide etchant. The Cr made an excellent hard mask in our process. Figure 1 is a scanning electron microscope SEM image of the 3-micrometers undercut of the SiO2 using the Cr hard mask, this undercut is expected with an isotropic wet etch. FABRICATION With the short loop experiments, described above and in last period, completed, we began full loop wafer processing using the previously developed process flow which incorporates two wafers, one silicon double-sided polished DSP and one silicon-on-insulator SOI, which will be bonded together using our EVG wafer-to-wafer bonding tool to complete the devices.
- Electrical and Electronic Equipment
- Electrooptical and Optoelectronic Devices