Abstract
The effects of arsenic concentration profiles in gate oxides on the electrical properties of metal-oxide-silicon (MOS) capacitors were investigated. It is found that arsenic in the bulk of gate oxide degrades the electric property of MOS devices, which could be due to the electron traps introduced by arsenic. Interestingly, the electric properties of MOS devices can be improved by an increase in the arsenic concentration at the SiO 2 /Si interface. This improvement may be attributed to the interfacial strain relaxation and/or the replacement of nonbridging bonds. The arsenic concentration profile in gate oxide plays a crucial role for the electric properties of MOS devices. © 2001 American Institute of Physics.