Modified gate processing for optimized definition of array and logic devices on same chip

Abstract

Two different gate conductor dielectric caps are used in the array and support device regions so that the bitline contact can be fabricated in the array region, but a thinner hard mask can be used for better linewidth control in the support device region. The thinner dielectric cap is made into dielectric spacers in the array device regions during support mask etching. These dielectric spacers allow for the array gate conductor resist line to be made smaller than the final gate conductor linewidth. This widens the array gate conductor processing window. The second dielectric cap layer improves linewidth control for the support devices and the array devices. Two separate gate conductor lithography steps and gate conductor dielectric etches are carried out in the present invention to optimize the gate conductor linewidth control in the array and support device regions. The gate conductors in the array and support devices regions are etched simultaneously to reduce production cost. In additional embodiments of the invention, dual workfunction support device transistors with or without salicide can be fabricated with an array including borderless contacts.