In one embodiment, the present invention relates to a method of forming a flash memory cell involving the steps of: forming a tunnel oxide on a substrate; forming an in situ phosphorus doped polysilicon layer over the tunnel oxide by low pressure chemical vapor deposition at a temperature between about 610.degree. C. and about 630.degree. C., wherein the in situ phosphorus doped polysilicon layer comprises from about 1.times.10.sup.19 atoms/cm.sup.3 to about 5.times.10.sup.19 atoms/cm.sup.3 of phosphorus; forming an insulating layer over the in situ phosphorus doped polysilicon layer; forming a conductive layer over the insulating layer; etching the in situ phosphorus doped polysilicon layer, the conductive layer and the insulating layer, thereby defining one or more stacked gate structures; and forming a source region and a drain region in the substrate, wherein the source region and the drain region are self-aligned by the stacked gate structures, thereby forming one or more memory cells.
A method of forming a gate of a semiconductor device, including the steps of sequentially forming a tunnel oxide film, a nitride film, a dielectric layer, a polysilicon layer, a metal silicide film, and a hard mask film on a semiconductor substrate; sequentially etching the hard mask film, the metal silicide film, the polysilicon layer, and a predetermined region of the dielectric layer, forming a control gate pattern and also exposing the nitride film; performing a thermal oxidization process on both sides of the control gate pattern, forming an oxide film; and stripping the exposed nitride film by a wet etch process, thereby exposing the tunnel oxide film.
Methods and arrangements that increase the process control during the fabrication of the control gate configuration in a non-volatile memory semiconductor device are provided. The methods and arrangements effectively prevent cracks from developing within a tungsten suicide layer that is part of a control gate structure within a non-volatile memory cell. Cracks within the tungsten silicide layer can affect the performance of the memory cell by increasing the resistance of the control gate configuration. The methods and arrangements prevent cracking of the tungsten silicide layer by minimizing the relative difference between temperatures associated with the deposition of the tungsten suicide layer and deposition of a subsequent overlying cap layer.
A method of forming a flash memory cell includes providing a substrate, forming an oxide layer over the substrate, forming a polysilicon floating gate over the oxide layer including providing a bottom seed layer having microcrystalline polysilicon, providing an upper amorphous silicon layer over the bottom seed layer, and annealing the upper amorphous silicon layer, providing an inter-poly dielectric layer over the floating gate, and forming a polysilicon control gate over the inter-poly dielectric layer.
A method and system for providing a semiconductor device is described. The semiconductor includes a core and a periphery. The method and system include providing a plurality of core gate stacks in the core, a plurality of sources in the core and a plurality of periphery gate stacks in the periphery. Each of the plurality of core gate stacks includes a first polysilicon gate and a WSi layer above the first polysilicon gate. The plurality of sources resides between a portion of the plurality of core gate stacks. Each of the plurality of periphery gate stacks includes a second polysilicon gate and a CoSi layer on the second polysilicon gate.
Methods of manufacturing flash memory cells. During a cleaning process after an etching process for forming a control gate is performed, polymer remains at the sidewall of a tungsten silicide layer. Therefore, the sidewall of the tungsten silicide layer is protected from a subsequent a self-aligned etching process. In addition, upon a self-aligned etching process, the etch selective ratio of the tungsten silicide layer to a polysilicon layer is sufficiently obtained using a mixed gas of HBr/O.sub.2. Therefore, etching damage to the sidewall of the tungsten silicide layer can be prevented. As a result, reliability of the process and an electrical characteristic of the resulting device are improved.
