Patent ID: 6921680
Filing Date: 2005-07-26
Classification: B81C

Abstract:
1. A process for fabricating and lubricating a DMD MEMS device, comprising the steps of: fabricating a CMOS memory structure in a silicon substrate; applying a thick oxide isolation layer over said silicon substrate; chemical mechanical polishing the surface of said oxide layer to provide a flat surface to fabricate the DMD superstructure; depositing, patterning, and etching of a metal-3 Aluminum layer on top of said polished surface of said oxide layer; spin-coating, lithographically patterning, and hardening a first organic sacrificial layer on top of said micro-planarized metal-3 layer, leaving vias for metal support posts; sputter-depositing a thin metal layer on top of said sacrificial layer; plasma-depositing a layer of SiO sputter-depositing a thicker layer of Aluminum covering said hinge metal and hinge oxide mask, said layer being patterned and plasma-etched to form a thin metal hinge and attached thick metal yoke structure and mirror address electrodes; spin-coating, lithographically patterning, and hardening a second organic sacrificial layer on top of said hinge and yoke structure, leaving vias for posts to support mirrors above said hinge and yoke structure; sputter-depositing Aluminum mirror metal layer over said second sacrificial layer, filling said mirror support post vias; plasma-depositing a layer of SiO partial sawing said wafer to define individual spatial light modulator chips; plasma-etching said first and second sacrificial layers from underneath said mirror structures leaving said mirrors suspended by said yoke/hinge/post structures; passivating the surfaces of all DMD chips on said wafer using a controlled, uniform nebulization process; performing an initial functional test on said DMD chips; breaking wafer of chips into individual DMD chips; die attaching said DMD chips in a package and connecting bond pads to package leads; performing a plasma activation on said packaged DMD chips; passivating the surfaces of individual DMD chips using a controlled, uniform nebulization process; applying an optical clear glass window/lid to package; performing burn-in on and final test on said DMD chips; said passivation nebulization process further comprising the steps of: supplying a lubricant to a first input of a nebulizer drift tube; supplying N the drifting of said expanded mist along said drift tube, down through an opening in the bottom of said drift tub; through the small end of an upside down funnel located at the top of a nebulizer passivation chamber; said mist striking the top convex spherical surface of a turbulation baffle, attached to the wall of said funnel at one or more points so as to leave a gap around the majority of the circumference of said baffle, said mist falling around the edge of said baffle; supplying N inserting a MEMS device specimen into the device exchanger at the bottom of a nebulizer passivation chamber; moving and scaling said MEMS device into the exposure aperture of said chamber; said passivant droplets coming in contact with the surfaces of said MEMS device, thereby uniformly lubricating said surfaces to prevent sticking of moving parts.