Method of making SRAM cell and structure with polycrystalline p-channel load devices

摘要

A method for forming a SRAM structure with polycrystalline P-channel load devices of an integrated circuit, and an integrated circuit formed according to the same, is disclosed. A field oxide region is formed over a portion of the substrate. A first gate electrode of a first N-channel field effect device is formed over the substrate having a source/drain region in the substrate. A second gate electrode of a second N-channel field effect device is also formed over the substrate and a portion of the field oxide. A first insulating layer is formed over the integrated circuit containing an opening exposing a portion of the source/drain region and the second gate electrode of the first and second N-channel devices respectively. An interconnect layer having a doped polysilicon layer and a barrier layer is formed over the integrated circuit, patterned and etched to define a shared contact region covering the exposed source/drain region and the second gate electrode of the N-channel devices. A second insulating layer is formed over the integrated circuit having an opening exposing a portion of the interconnect layer. A first conductive layer is formed over the integrated circuit, patterned and etched to define a first and a second gate electrode of a first and a second P-channel field effect device respectively. A gate oxide layer is formed over a portion of the first gate electrode and a portion of the second gate electrode of the first and second P-channel devices. A second conductive layer is formed over the integrated circuit, patterned and etched to define a source/drain and channel region of the first gate electrode of the first P-channel device and covering a portion of the second gate electrode of the second P-channel device.