Abstract:
A silicon substrate with a GaN-based device and a Si-based device on the silicon substrate is provided. The silicon substrate includes the GaN-based device on a SiC crystalline region. The SiC crystalline region is formed in the silicon substrate. The silicon substrate also includes the Si-based device on a silicon region, and the silicon region is next to the SiC crystalline region on the silicon substrate.
Abstract:
The mechanisms of forming SiC crystalline regions on Si substrate described above enable formation and integration of GaN-based devices and Si-based devices on a same substrate. The SiC crystalline regions are formed by implanting carbon into regions of Si substrate and then annealing the substrate. An implant-stop layer is used to cover the Si device regions during formation of the SiC crystalline regions.
Abstract:
The process methods and structures mentioned above for creating a trench MOSFET enables self-aligned contacts to be formed to allow decreasing pitch size for trench MOSFET. The self-aligned contacts are formed by etching exposed silicon areas without using lithographical mask and alignment. As a result, the allowance for alignment can be saved and the pitch size can be decreased.
Abstract:
A method and resulting structure for defining a dielectric layer thickness and etching openings having a desired aspect ratio through said dielectric layer covering regions in the peripheral circuits of a DRAM integrated circuit to be electrically contacted in a semiconductor wafer is described. The DRAM integrated circuit including the peripheral circuits to be electrically contacted is provide in the semiconductor wafer. A first conductive polysilicon layer is formed over said DRAM integrated circuit and the layer is patterned to leave the layer over the peripheral circuits. A first interlevel dielectric layer is formed over the polysilicon layer which has been patterned. A second conductive polysilicon layer is formed over the first interlevel dielectric layer and patterned to leave the layer over areas other than the peripheral circuits. The first interlevel dielectric layer and first polysilicon layer thereunder are masked and etched to remove the first interlevel dielectric layer and first polysilicon layer from all the peripheral circuits. A second interlevel dielectric layer is formed over the exposed second conductive polysilicon layer, first interlevel dielectric and semiconductor wafer. The openings having a desired aspect ratio are etched through said second interlevel dielectric layer.