High-performance mid-wavelength InAs avalanche photodiode using AlAs_0.13Sb_0.87 as the multiplication layer

Abstract

We report on a high-performance mid-wavelength infrared avalanche photodetector (APD) with separate absorption and multiplication regions. InAs is used as the absorber material and high-bandgap <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="m1"> <mml:mrow> <mml:msub> <mml:mi>AlAs</mml:mi> <mml:mn>0.13</mml:mn> </mml:msub> <mml:msub> <mml:mi>Sb</mml:mi> <mml:mn>0.87</mml:mn> </mml:msub> </mml:mrow> </mml:math> is used as the multiplication material. At room temperature, the APD’s peak response wavelength is 3.27 μm, and the 50% cutoff wavelength is 3.5 μm. The avalanche gain reaches 13.1 and the responsivity is 8.09 A/W at 3.27 μm when the applied reverse bias voltage is 14.6 V. The measured peak detectivity <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="m2"> <mml:mrow> <mml:msup> <mml:mrow> <mml:mi>D</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>⋆</mml:mo> </mml:mrow> </mml:msup> </mml:mrow> </mml:math> of the device is <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="m3"> <mml:mrow> <mml:mn>2.05</mml:mn> <mml:mo>×</mml:mo> <mml:msup> <mml:mrow> <mml:mn>10</mml:mn> </mml:mrow> <mml:mrow> <mml:mn>9</mml:mn> </mml:mrow> </mml:msup> <mml:mtext> </mml:mtext> <mml:mi>cm</mml:mi> <mml:mo>·</mml:mo> <mml:msup> <mml:mrow> <mml:mi>Hz</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>0.5</mml:mn> </mml:mrow> </mml:msup> <mml:mo>/</mml:mo> <mml:mi mathvariant="normal">W</mml:mi> </mml:mrow> </mml:math> at 3.27 μm.