| Summary: | 碩士 === 國立成功大學 === 電機工程學系 === 85 ===
A detail study has been made of the current-voltage characteristics of Hg1-xCdxTe ion-implanted p-n junctions with x□0.22. It is found that the dark currents, can be represented three current components over a broad range of voltage and temperature. A diffusion current dominates in the small bias region and high temperature. On the other hand, trap-assisted tunneling play an important role in the medium reverse bias region and medium temperature. Band-to-band tunneling is the key leakage current sourc in the high reverse bias and low temperature. In addition, diffusion current is the dominant current component limiting the zero bias resistance area (R0A) product down to 90k. The generation-recombination mechanism fits the transition line below 90k. At lower temperature, R0A product became temperature insensitive, the properties of this current mechanism can be accounted for tunneling mechanism.
We have also presented the results of experiments to characterized 1/f noise of HgCdTe photodiode. In this experiments, the 1/f noise was measured as a function of temperature, diode bias voltage, Since these parameters varied the relative contributions of the various current mechanisms, the diode current mechanism responsible for 1/f noise was isolated.
The maximum value of specific detectivity (D*) is 3.51×1010 cm.Hz1/2/W at 50 mV reverse bias.
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