A simple on-wafer monitoring device that we developed showed that the increase in electrical current in silicon dioxide film corresponded completely to the increase in interface states at the interface between silicon dioxide and silicon under plasma irradiation, as measured by a charge pumping current method in a metal-oxide-semiconductor transistor. Using an electron spin resonance spectrometer, we found that the E′ centers in the silicon dioxide also increase. An experiment using helium (He), argon (Ar), and oxygen (O2) plasmas showed that the electrical current, interface states, and E′ centers depend on the wavelength of vacuum ultraviolet protons in the plasma. Under the same plasma density, the plasma-induced current in He plasma is the largest of the three gas plasmas. In the same way, the interface states and E′ centers increased the most for He plasma. This strongly implies that the plasma-induced carriers (holes and electrons) that generate the electrical current in the insulator directly or indirectly affect the bonding of silicon to oxygen in Si O2 and the increase in the interface states at the boundary between Si O2 and Si in metal-oxide-semiconductor (MOS) devices. The simple on-wafer monitoring for plasma-induced current that we developed can predict the generation of Si O2 -Si interface states as plasma-induced damage in MOS devices.
|Number of pages||5|
|Journal||Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures|
|Publication status||Published - 2005 Dec 1|
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Surfaces and Interfaces
- Physics and Astronomy (miscellaneous)