摘要 |
A method for forming a DRAM capacitor that utilizes silicon nitride spacers on two occasions to perform self-aligned contact window etching operations. Furthermore, on the second etching operation, one less photomask is required for the etching of the second via. In addition, a silicon nitride layer over the first polysilicon layer has a smaller thickness than the usual oxide layer in a conventional method of manufacture. Consequently, a shallower contact step height for the capacitor, which is beneficial to the production of miniaturized devices, is obtained. Finally, the tri-fork shaped capacitor structure further increases the surface area of the capacitor so that the capacitance of the DRAM capacitor is increased.
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