What is an uncooled "nanowire" short-wave infrared photodiode? The term is very long, and it seems a bit difficult to understand, but in fact, this is only one of the photodiodes, and it is proposed for the application of infrared sensors that cannot be separated from cooling and other restrictions. Next, I will discuss this kind of component with you.

　　The problem of refrigeration has always been a concern of infrared sensor researchers. The SWIR and MWIR detectors that are not cooled at room temperature are composed of InAs or InAsSb nanowire arrays grown vertically on an indium phosphide substrate, so that the combination of the nanowires and the substrate produces an InAs-InP heterojunction, which can then be paired with alumina This structure is passivated, thereby reducing non-radiative recombination on the surface of the nanowire.

The calculation results show that, compared with the planar uncooled InAs photodiode, the plasma mode resonance peak D* of the uncooled InAs(Sb)-InP nanowire heterojunction photodiode can reach 3.5×1010cmHz1/2W-1, which is almost It is 10 times that of a planar photodiode.

　　 Researchers fabricated nanowire photodetectors according to the previously developed standard process. The nanowires were grown on patterns optimized for photodetection in the appropriate wavelength range, and then passivated with Al2O3. Subsequently, the passivation layer at the tip of the nanowire is removed. Using the nanowire itself as a shield, gold is deposited on the bearing surface of the nanowire, and then a series of nanoholes are formed in the gold to form a plasma grating. The grid is very important: it enhances the coupling of incident light to the tip of the nanowire through plasmon resonance.