摘要:
A method is disclosed to form a reliable silicon nitride spacer between the lower edges of the floating gate and the control gate of a split-gate flash memory cell. This is accomplished by forming a floating gate with vertical sidewalls, forming a high temperature oxide layer followed by silicon nitride layer over the floating gate including the vertical sidewalls, ion implanting the nitride layer and then selectively etching it to form a robust silicon nitride spacer of well defined rectangular shape.
摘要:
A method is provided for forming a plurality of structures with different resistance values in a single polysilicon film as follows. Form a polysilicon layer upon a substrate. Pattern the polysilicon to expose a portion thereof which is to be reduced in thickness. Partially etch through the polysilicon to produce a reduced thickness thereof while leaving the remainder of the polysilicon with the original thickness. Dope the polysilicon layer through the polysilicon with variable doping as a function of the reduced thickness and the original thickness of the polysilicon.
摘要:
A device with a plurality of structures with different resistance values is formed on a substrate. A polysilicon layer is formed upon the substrate. A silicon oxide layer is formed over the substrate. A hard masking layer is formed over the silicon oxide layer. The hard masking layer includes a full thickness portion and a thinner portion. The polysilicon layer below the full thickness portion is lightly doped forming a high resistance region. Below the thinner portion the polysilicon layer is heavily doped forming a low resistance region. However, in spite of the differences in resistance, the high resistance region and the low resistance region have the same thickness.
摘要:
A method for forming a CMOS image sensor spacer structure. A polysilicon gate electrode is formed on a substrate; a thin layer of first dielectric is deposited over the exposed surfaces of the gate electrode and the top of the substrate. Next a second layer of dielectric is deposited after which etching is performed to create the electrode spacer. The deposited second layer of dielectric serves as an etch stop and prevents damage to the substrate surface between spacers of the gate electrodes. An alternate method uses a thin ply layer as the stop layer and, in so doing, source/drain damage caused by the white pixel problem.
摘要:
A method is disclosed to form a reliable silicon nitride spacer between the lower edges of the floating gate and the control gate of a split-gate flash memory cell. This is accomplished by forming a floating gate with vertical sidewalls, forming a high temperature oxide layer followed by silicon nitride layer over the floating gate including the vertical sidewalls, ion implanting the nitride layer and then selectively etching it to form a robust silicon nitride spacer of well defined rectangular shape.
摘要:
This method forms structures with different resistance values from a single polysilicon film formed on a substrate. Form a hard masking layer on the polysilicon film. Form a photoresist mask over the hard masking layer. Partially etch the hard masking layer through the photoresist mask to reduce the thickness of the polysilicon while leaving the remainder of the hard masking layer with the original thickness. The thickness is reduced in locations where a low resistance is to be located in the polysilicon film. Then dope the polysilicon layer through the hard masking layer with variable doping as a function of the reduced thickness and the original thickness of the hard masking layer.
摘要:
A method for passivating a target layer. There is first provided a substrate. There is then formed over the substrate a target layer, where the target layer is susceptible to corrosion incident to contact with a corrosive material employed for further processing of the substrate. There is then treated, while employing a first plasma method employing a first plasma gas composition comprising an oxidizing gas, the target layer to form an oxidized target layer having an inhibited susceptibility to corrosion incident to contact with the corrosive material employed for further processing of the substrate. Finally, there is then processed further, while employing the corrosive material, the substrate. The method is useful when forming bond pads within microelectronic fabrications. When directed towards forming patterned conductor layers, such as bond pads, the method optionally employs an inert plasma treatment of a patterned conductor layer followed by an aqueous ethanolamine treatment of the patterned conductor layer prior to a first plasma treatment of the patterned conductor layer.
摘要:
A method to prevent threshold shifts in MOS transistors due to auto-doping from heavily doped polysilicon layers. Isolation regions are provided in a semiconductor substrate separating active areas. A gate oxide layer is formed over the surface of the semiconductor substrate. A polysilicon layer is deposited overlying the gate oxide layer. A tungsten silicide layer is deposited overlying the polysilicon layer. The tungsten silicide layer and the first polysilicon layer are etched to form MOS gates and bottom electrodes for dual polysilicon capacitors. An interpoly dielectric layer is deposited overlying entire surface of the semiconductor substrate. A doped polysilicon layer is deposited overlying the interpoly dielectric layer. A sealing oxide layer is deposited overlying the doped polysilicon layer to prevent out-diffusion of impurity ions into the semiconductor substrate and thereby preventing auto-doping. The tungsten silicide layer is annealed. Ions are implanted to form drain and source regions. The fabrication of the integrated circuit device is completed.
摘要:
A process for creating field oxide isolation for the micron and sub-micron devices in the high density integrated circuits has been developed. The junction leakage problem resulted from the trenches in the substrate formed after the removal of the silicon nitride mask, is avoided. The encroachment of the "bird's beak" into the small active device region is also minimized by this invention. These goals are accomplished by the addition of a polysilicon or amorphous silicon refill layer in the trenches after the removal of the silicon nitride oxidation mask in the isolation region, prior to field oxide oxidation process.
摘要:
A method for etching bonding pad access openings in a passivation layer of an integrated circuit is described. The method utilizes a two step etching procedure wherein the first step etches isotropically through a major portion of the passivation layer under conditions which provide very high etch rate selectivities of the passivation material to the photoresist. These high selectivitities result in virtually no erosion of the photoresist while the greater part of the opening is etched. A second anisotropic etch step wherein the base of the access opening is defined faithfully replicates the dimensions of the mask pattern. This two step etch process permits the use of photoresist layers of moderate thickness as well as photoresist layers with thin regions, such as occur when the photoresist is deposited over the uneven surface topography typically found on unplanarized passivation layers. The minimal erosion of the photoresist during the isotropic etch step secures sufficient photoresist coverage in the thin regions to prevent penetration and attack of passivation over wiring lines in the uppermost wiring level of the integrated circuit.