摘要:
A process for forming a MOSFET device, featuring a heavily doped source/drain region, isolated from a semiconductor substrate, via use of a thin silicon oxide layer, has been developed. After formation of a lightly doped source/drain region, an opening is created in the semiconductor substrate, in a region between insulator spacers, on a gate structure, and insulator filled, shallow trench regions, resulting in lightly doped source/drain segments, remaining under the masking insulator spacers. After a thin silicon oxide layer is formed on the exposed silicon surfaces, in the openings, a silicon deposition, and etch back procedures are performed, partially refilling the openings to a depth that still allows the thin silicon oxide layer to be exposed on the sides of the lightly doped source/drain segment. After removal of the exposed portion of the thin silicon oxide layer, and after deposition and etch back of another silicon layer, completely filling the openings, a heavily doped source/drain region is formed in the silicon layers, residing in the openings.
摘要:
An integrated process for forming a 4T SRAM and a mixed-mode capacitor, with logic, on the same integrated circuit, is provided. A semiconductor substrate is provided having field isolation regions, with a gate and gate oxide between the field isolation regions. Polysilicon interconnects are formed over a portion of the field isolation regions, only in a first memory region, and a bottom capacitor plate over a field oxide region in a capacitor region. Active regions are formed in the substrate, adjacent to each gate. Insulating spacers are formed on the sidewalls of the gates, polysilicon interconnects and the floating gate, and later removed from the interconnect. A layer of titanium silicide is formed over the gates and capacitor bottom plate, and also over the polysilicon interconnects and active regions. An interpoly oxide is formed over the semiconductor substrate. An opening is formed in the interpoly oxide over the polysilicon interconnect. A second layer of polysilicon is deposited over the substrate. The second layer of polysilicon is patterned to form a top capacitor plate, and to form a load resistor for the SRAM.
摘要:
A semiconductor fabrication process has been developed in which both DRAM and logic device structures are integrated on a single silicon chip. The process features combining process steps for both device types, while using only a single level of polysilicon for both a high capacity DRAM cell, as well as for a CMOS logic cell. The high capacity DRAM cell is composed of an overlying polysilicon storage gate structure, a thin dielectric layer, and an underlying doped semiconductor regions.
摘要:
An integrated process for forming a 4T SRAM and a floating gate memory, with logic, on the same integrated circuit, is provided. A semiconductor substrate is provided having field isolation regions, with a gate and gate oxide between the field isolation regions. Polysilicon interconnects are formed over a portion of the field isolation regions, only in a first memory region, and a floating gate over a field oxide region in a second memory region. Active regions are formed in the substrate, adjacent to each gate. Insulating spacers are formed on the sidewalls of the gates, polysilicon interconnects and the floating gate, and later removed from the interconnect. A layer of titanium silicide is formed over the gates, except over the floating gate in the second memory region, and also over the polysilicon interconnects and active regions. An interpoly oxide is formed over the semiconductor substrate. An opening is formed in the interpoly oxide over the polysilicon interconnect. A second layer of polysilicon is deposited over the substrate. The second layer of polysilicon is patterned to form a control gate over the floating gate, and to form a load resistor for the SRAM.
摘要:
This method forms a capacitor structure on a semiconductor substrate for providing split voltages for semiconductor circuits by the following steps. Form an active area in the substrate serving as a lower capacitor plate for a bottom capacitor and then form a thin dielectric layer and field oxide regions on the substrate, and cover the dielectric layer with a capacitor plate over the active area to complete the bottom capacitor. Form a thick dielectric layer over the device and a via through the thick dielectric layer to the upper capacitor plate. Form a second lower plate for a top capacitor. Form an inter-layer dielectric layer over the second lower plate. Form an upper capacitor layer over the inter-layer dielectric layer to form a top capacitor with a different capacitance value from the bottom capacitor. The value of the capacitance can be varied by selection of the permittivity and/or thickness of the dielectric layer and by variation of the effective plate area of the top and bottom capacitors.
摘要:
A semiconductor fabrication process has been developed in which both DRAM and logic device structures are integrated on a single silicon chip. The process features combining process steps for both device types, while using only a single level of polysilicon for both a high capacity DRAM cell, as well as for a CMOS logic cell. The high capacity DRAM cell is composed of an overlying polysilicon storage gate structure, a thin dielectric layer, and an underlying doped semiconductor regions.
摘要:
A method of forming a local interconnect in an SRAM, simultaneously with the formation of a salicide in logic devices on the same semiconductor substrate, is described. A semiconductor substrate on which MOS (Metal Oxide Semiconductor) transistors have been formed is provided. The transistors are separated by field isolation regions, and each transistor has a gate overlying a gate oxide and has source and drain regions in the substrate. Spacers are provided on the sidewalls of the gates, and some of the field oxide regions in the SRAM have polysilicon interconnects, with sidewall spacers. The sidewall spacers are removed from the polysilicon interconnects. A layer of titanium is deposited over the semiconductor substrate. A salicide is formed over the gates, the source and drain regions, and the polysilicon interconnects, so that the local interconnect is formed connecting the polysilicon interconnects to one of the source regions.
摘要:
A method for forming thick field oxide regions, to be used for isolation in MOSFET memory regions, while also forming insulator filled, narrow trenches, to be used for isolation purposes in MOSFET logic regions, has been developed. The fabrication process features initially creating thick field oxide regions, in the MOSFET memory region, obtained via thermal oxidation procedures, followed by creation of a narrow trench opening, in the MOSFET logic region. An ozone aided, silicon oxide, CVD deposition, is used to fill the narrow trench openings, followed by a selective chemical mechanical polishing procedure, used to remove unwanted regions of silicon oxide layer, creating an insulator filled, narrow trench isolation, in the MOSFET logic region.
摘要:
A method is described for fabricating a lightly doped drain MOS FET integrated circuit device which is useful for sub-half micron ground rules integrated circuits. A pattern of gate electrode structures is formed upon a semiconductor substrate which structures each includes a gate oxide and a polysilicon layer. A pattern of lightly doped regions in the substrate are formed under the structures by multiple ion implantations. After the ion implantations the lightly doped regions are annealed at a temperature and time to cause a critical and desired dopant diffusion. A dielectric spacer structure is formed upon the sidewalls of each of the structures and over the adjacent portions of the substrate. A pattern of heavily doped regions is formed in the substrate adjacent to the dielectric spacer structure on the sidewalls of the structures and over the adjacent portions of the substrate which form lightly doped drain source/drain structures of an MOS FET device to form said integrated circuit device.
摘要:
An improved structure and method of forming a protective layer over an opening in insulation layers over a fuse is presented. The protective layer prevents contaminates from entering the exposed insulation layers in a fuse opening while not interfering with the laser trimming of the fuse. An opening through the layers over a fuse is made forming vertical sidewalls which expose portions of the insulation layers. A protective layer is formed over the insulation layer, the sidewalls and fuse thus preventing contaminates from diffusing into the exposed insulation layers. A second opening is made in the protective layer over the fuse link to allow a laser beam to melt the underlying fuse link.