FABRICATION AND STRUCTURE OF ASYMMETRIC FIELD-EFFECT TRANSISTORS USING L-SHAPED SPACERS

摘要

A gate electrode (302) of a field-effect transistor (102) is defined above, and vertically separated by a gate dielectric layer (300) from, a channel-zone portion (284) of body material of a semiconductor body. Semiconductor dopant is introduced into the body material to define a more heavily doped pocket portion (290) using the gate electrode as a dopant-blocking shield. A spacer (304T) having a dielectric portion situated along the gate electrode, a dielectric portion situated along the body, and a filler portion (SC) largely occupying the space between the other two spacer portions is provided. Semiconductor dopant is introduced into the body to define a pair of source/drain portions (280M and 282M) using the gate electrode and spacer as a dopant-blocking shield. The filler spacer portion is removed to convert the spacer to an L shape (304). Electrical contacts (310 and 312) are formed respectively to the source/drain portions.