A drain forming process on an integrated circuit device and an integrated circuit device manufactured by the process

摘要

A method of using removable sidewall spacers to minimize the need for mask levels in forming lightly doped drains (LDDS) in the formation of CMOS integrated circuits. Aluminum or chemical vapor deposition (CVD) metals such as tungsten are suitable materials to form removable sidewall spacers which exist around CMOS gates during heavily doped source/drain region implants. Conformal materials such as CVD polysilicon may also be employed for this purpose. The sidewall spacers are removed before implantation of the lightly doped drain regions around the gates. This implantation sequence is exactly the reverse of what is currently practiced for lightly doped drain formation.