Patent ID: 6573187
Filing Date: 2003-06-03
Classification: H01L

Abstract:
A method of dual damascene patterning through the use of two contiguous dielectric layers, comprising the steps of:providing a substrate having two contiguous layers of dielectric deposited thereon, said two layers of dielectric comprising a first layer of dielectric and a second layer of dielectric, said first layer of dielectric having been deposited over the surface of said substrate, said second layer of dielectric having been deposited over the surface of said first layer of dielectric, said second layer of dielectric having an etch sensitivity that is larger than an etch sensitivity of said first layer of dielectric by a measurable amount; forming a first layer of photoresist on the surface of said second layer of dielectric; hole patterning said first layer of photoresist by exposing and wet developing said first layer of photoresist using a first mask; etching said two layers of dielectric using said patterned first layer of photoresist as a mask thereby transferring said hole pattern in said first layer of photoresist into said second and into said first layer of dielectric, forming a hole pattern in said first and said second layer of dielectric; removing said first layer of photoresist; forming a second layer of photoresist on the surface of said second layer of dielectric; line patterning said second layer of photoresist by exposing and wet developing said second layer of photoresist using a second mask; etching said second layer of dielectric using said patterned second layer of photoresist as a mask, transferring said line pattern in said second layer of photoresist into said second layer of dielectric, forming a line pattern in said second layer of dielectric, said line pattern in said second layer of dielectric replacing said hole pattern in said second layer of dielectric; removing said second layer of photoresist; and depositing metal into said line pattern in said second layer of dielectric and said hole pattern in said first layer of dielectric to form a dual damascene structure and planarizing said two layers of dielectric.