STAIRCASE AVALANCHE PHOTODIODE WITH A STAIRCASE MULTIPLICATION REGION COMPOSED OF AN AlInAsSb ALLOY

摘要

A staircase avalanche photodiode with a staircase multiplication region composed of an AlInAsSb alloy. The photodiode includes a buffer layer adjacent to a substrate and an avalanche multiplication region adjacent to the buffer layer, where the avalanche multiplication region includes a graded AlInAsSb alloy grown lattice-matched or psuedomorphically strained on either InAs or GaSb. The photodiode further includes a photoabsorption layer adjacent to the avalanche multiplication region, where the photoabsorption layer is utilized for absorbing photons. By utilizing AlInAsSb in the multiplication region, the photodiode exhibits a direct bandgap over a wide range of compositions as well as exhibits large conduction band offsets much larger than the smallest achievable bandgap and small valance band offsets. Furthermore, the photodiode is able to detect extremely weak light with a high signal-to-noise ratio.

主权项

1. A photodiode, comprising:
an avalanche multiplication region, wherein said avalanche multiplication region comprises a graded aluminum indium arsenide antimonide (AlInAsSb) alloy grown lattice-matched or psuedomorphically strained on either indium arsenide (InAs) or gallium antimonide (GaSb), wherein said graded avalanche multiplication region comprises multiple steps in which a bandgap is varied from small to large and vice-versa; and a photoabsorption layer for absorbing photons.