Patent ID: 6248618
Filing Date: 2001-06-19
Classification: H01L,Y10S

Abstract:
A method of forming thick and thin gate oxides for CMOS devices, the steps comprising:providing a silicon semiconductor substrate having first and second active areas, said first and second active areas being separated by shallow trench isolation regions;forming selective oxide growth over said first active area by UV oxidation to form a first gate oxide layer having a first thickness, wherein said UV oxidation is performed through a mask positioned between an ultraviolet source and said silicon semiconductor substrate, and wherein said mask having an opening that exposes said first active area; andsimultaneously oxidizing said first and second active areas; said first thickness of said first gate oxide layer increasing to a second thickness, and a second gate oxide layer having a predetermined thickness is formed in said second active area;whereby said second thickness of said first gate oxide layer is greater than said thickness of said second gate oxide layer.