A design and implementation methodology for micromachining

The use of standard CMOS processes for micromachining has certain limitations, such as the incompatibility of aluminum bonding pads with the most popular silicon etchants, and the difficulty of obtaining backside patterns on individual die. To overcome these limitations, the Canadian Microelectronics Corporation is developing the Can-MEMS post-processing service, leveraging equipment and expertise at various institutions in Canada. Using a distributed lab to post-process wafers from a CMOS foundry, several features are being offered: (i) a third metal layer (platinum); (ii) a silicon nitride passivation layer; (iii) backside patterning; (iv) anisotropic wet etching of silicon. Design rules for use with these new features have been developed