Hg/sub 0.56/ Cd/sub 0.44/ Te 1.6- to 2.5- mu m avalanche photodiode and noise study far from resonant impact ionization

An investigation was made on the avalanche multiplication and impact ionization processes in p-n/sup -/-n/sup +/ junctions formed in Hg/sub 0.56/Cd/sub 0.44/Te solid solutions. Photocurrent multiplication was determined at 300 K in planar p-n/sup -/-n/sup +/ structures characterized by a breakdown voltage of 30 V. The experimental results were used to calculate the electron, alpha , and hole, beta , ionization coefficients. It was found that alpha is greater than beta because Delta , the spin-orbit splitting energy, is higher than the bandgap energy. These experimental results were in satisfactory agreement with multiplication noise measurements using separate electron and hole injection.<
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