Evaluation of Qss on SOI back Si/SiO2 interface by newly designed charge pumping method-TEG

The surface state density (Qss) of SOI back Si/SiO
₂
interface was evaluated by newly designed Charge Pumping (CP) method-TEG. The CP method was also re-examined to apply to the thick oxide MOS. It was noted that the high voltage amplitude and attention on the slope on the gate pulse are necessary to evaluate the Qss of SOI back interface made of the thick oxide. It was founded out that the Qss of SOI back interface (bonded wafer interface) is comparable to that of the thermal oxidation interface and also that the Qss of Floating Zone (FZ) wafer is larger than that of Czochralski (CZ) wafer, and the Qss of FZ wafer varies from lot to lot.