MEMS devices monolithically integrated with drive and control circuitry
View Patent ↗Described are MEMS mirror arrays monolithically integrated with CMOS control electronics. The MEMS arrays include polysilicon or polysilicon-germanium components that are mechanically superior to metals used in other MEMS applications, but that require process temperatures not compatible with conventional CMOS technologies. CMOS circuits used with the polysilicon or polysilicon-germanium MEMS structures use interconnect materials that can withstand the high temperatures used during MEMS fabrication. These interconnect materials include doped polysilicon, polycides, and tungsten metal.
1. A memory array comprising:
a. a plurality of bitlines;
b. a plurality of wordlines;
c. an array of transistors, each transistor including a first current-carrying terminal coupled to one of the bitlines, a second current-carrying terminal, and a control terminal coupled to one of the wordlines; and
d. an array of variable capacitors, each variable capacitor including a first capacitor electrode, coupled to a respective one of the second current-carrying terminals of the array of transistors, and a second capacitor electrode, wherein each of the variable capacitors exhibits a first capacitance with a first voltage applied between the first and second capacitor electrodes and a second capacitance with a second voltage applied between the first and second capacitor electrodes.
2. The memory array of claim 2 , each capacitor further comprising a hinge.
3. The memory array of claim 2 , wherein the hinge comprises a semiconductor.
4. The memory array of claim 3 , wherein the semiconductor is highly doped.
5. The memory array of claim 1 , wherein the first and second capacitor electrodes include a plurality of comb teeth.