Patent ID: 7935633
Filing Date: 2011-05-03
Classification: B81C,H01L

Abstract:
1. A method of fabricating an electronic memory, comprising: forming a substrate including an array of active electronic devices; forming at least one polysilicon layer on the substrate having a patterned photoresist layer on the at least one polysilicon layer; and patterning the polysilicon layer in a single step etch solution, comprising exposing the substrate having the patterned photoresist layer on the polysilicon layer for a predetermined time period to a liquid chemical etch solution containing at least tetra methyl ammonium hydroxide and water at a preselected temperature and first concentration, and at least a fixed percentage of an ammonium hydroxide solution, wherein the ammonium hydroxide solution is added to the tetra methyl ammonium hydroxide and water solution after the preselected temperature is obtained.