The Theoretical Analysis And Testing Of HgCdTe Loophole P-N Junction

In this dissertation, the HgCdTe loophole P-N junction is investigated mainly from analyzing and testing the I-V characteristic. The following is the main work and results:In theory: (l)the summarization is made of the HgCdTe linear gradient junction, and the characteristics of contact potential and the width of spatial electronic region varying with carrier density grads are obtained. (2) The R<,A of loophole P-N junction under ideal conditions limited by diffusion current is analyzed, and found that the loophole P-N junction has the same high theoretical upper limit valve, which supposing the HgCdTe loophole P-N junction is special vertical junction. (3) According with the dependence of generation-recombination current and diffusion current on temperature, the characteristic and function are set up between temperature and composition which equate the generation-recombination current to diffusion current in that to differentiating the leakage mechanism of loophole P-N junction.In experimental) The results obtained from testing between a electrode and some different elements indicate that the sample's leakage current is concerned with the area of element. (2). Variable temperature test is applied in this dissertation, and found the dominant current is surface current. (3). The test was made between the same element and different size electrodes. When the electrode's area is much larger than the elements, the effect of electrode's dimension is comparably small. (4). The abnormal phenomena in I-V characteristic test were investigated by theory and experiments, and found that the etching process is the main reason. (5). To adding test methods of device, we obtained the cutoff wavelength through series resistance, the results are less more than O.Sujn difference from that obtained by spectral response test.