SEMICONDUCTOR DEVICE AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device where problems of boron's piercing and NBTI(negative bias temperature instability) can be broken up, and to provide its manufacturing method. SOLUTION: A gate insulating film 12 and a gate electrode 8 are formed on a silicon substrate 1, and the gate insulating film 12 contains at least hafnium, oxygen, fluorine, and nitrogen. The concentration of fluorine is high near an interface with the silicon substrate 1 and reduces gradually as getting close to the gate electrode 8, and the concentration of nitrogen is high near an interface with the gate electrode 8 and reduces gradually as getting close to the silicon substrate 1. The concentration of fluorine near the interface with the silicon substrate 1 preferably is 1×1019cm-3or more. The concentration of nitrogen near the interface with the gate electrode 8 preferably is 1×1020cm-3or more. COPYRIGHT: (C)2006,JPO&NCIPI