| 摘要 |
PURPOSE:To measure deep impurity level information by analyzing the timing change signal of the electric capacity of a junction depletion layer via an analog function generator as a signal adapted for the analysis. CONSTITUTION:When the ionized net impurity density of a depletion layer is represented by N10, a capacitive change DELTAC(t)=C0[[1+NI(t)/NIO]<1/2>-1] can be obtained after t seconds from the injection of carrier. When reverse bias VR is applied to a specimen 1, a pulse 2 is applied to the specimen to obtain the DELTAC(t) by a capacity meter 3, is deformed via an analog function generator 4, and with f[DELTAC(t)]=[DELTAC(t)/C0]<2>+2DELTAC(t)/C0=DELTANI(t)/NIO, the timing change of the signal of [DELTAC(t)/C0]<2>+2DELTAC(t)/C0 is obtained at the prescribed temperature, the time constant becomes the reciprocal number of the thermal radiation rate based on the deep impurity level correctly. The output f[DELTAC(t)] of the function generator 4 can be readily analyzed by the conventional analyzer 5. Since the theoretical formula is analogously treated to a signal adapted for the analysis in this manner, the analysis can be accurate and ready. |
