In this thesis, the minority carrier lifetime of HgCdTe was measured using PCD(Photoconductive decay) method and the surface property of HgCdTe was analyzed quantitatively. In case of n-type MOVPE grown HgCdTe wafer the minority carrier lifetime of it was measured 350nsec when it was passivated with ZnS and 230nsec when it was not passivated, which means that surface recombination velocity was reduced drastically when it was passivated with ZnS. And it also proves that PCD method is a useful method for the surface property analysis of HgCdTe.
However, there are two problems in measuring the minority carrier lifetime of p-type LPE grown HgCdTe. One is that it is very difficult to make ohmic contact at both sides of p-type HgCdTe sample in order to measure the lifetime of it using PCD method. But, fortunately, if the variation of contact resistance according to voltage is far less than the change of bulk resistance by incident light on the sample, it can be neglected within experimental error.
The other problem is that the measurement range of minority carrier lifetime is limited by RC delay, which is occurred by parasitic capacitance in the system. Presently the parasitic capacitance of the system is about 100pF and in case of p-type LPE HgCdTe sample the RC delay is about 20nsec. So the minority carrier lifetime which is less than 20nsec cannot be measured for the time being. It is a serious problem because the lifetime of p-type HgCdTe is assumed about several nsec to several tens nsec. But if the parasitic capacitance is reduced, for example, by modifying dewar, this problem will be solved satisfactorily.
