INFLUENCE OF BACKSURFACE ARGON BOMBARDMENT ON SIO2-SI INTERFACE CHARACTERISTICS

A low-energy (550 eV) argon-ion beam was used to directly bombard the backsurface of polysilicon-gate metal-oxide-semiconductor (MOS) capaci tors after the completion of all conventional processing steps. The in terface characteristics of the MOS capacitors were investigated. The r esults show that, as the bombardment dose increases, the active dopant concentration near the oxide-semiconductor interface gets higher; max imum midgap energy increases; and interface-state density becomes lowe r. This simple technique is compatible with existing integrated-circui t processing, and can easily improve the interface characteristics, an d therefore the electrical characteristics of MOS devices. (C) 1996 Am erican Institute of Physics.