Two signals from silicon nitride (Si
3N
4) film have been measured by the electron spin resonance (ESR) method at very low temperature of about 10 K. The two signals correspond to silicon dangling bonds of an Si
3Si
0 state and an N
3Si
0 state. The total spin density is about 2×10
17 cm
-3. The evaluation of metal-nitride-oxide-silicon (MNOS) non-volatile memory devices has revealed that Si
3N
4 film has electron traps of about 7×10
18 cm
-3 and hole traps of about 1.2×10
20 cm
-3. These results have led us to believe in the coexistence of Si
3Si
+ and N
3Si
-, which are not measured by the ESR method in the equilibrium state. Thus, an electron-trapped state represents a negatively charged state of the coexisistence of Si
3Si
0 and N
3Si
-, and a holetrapped state represents a positively charged state of the coexisistence of Si
3Si
+ and N
3Si
0. We, therefore, propose a 2-trap model in which electrons and holes are separately trapped.
抄録全体を表示