Abstract:
The technology has been developed for producing bridge-type photodiodes with a small photosensitive area diameter ($<$100 $\mu$m) based on InAs/InAsSbP heterostructures, enabling high reproducibility of device parameters. It has been shown that complete isolation of the metal bridge during etching allows for a halving of the mesa height, thereby ensuring greater mechanical strength of the bridge photodiode. The use of the proposed technology has resulted in a reduction in the device parameter spread across the wafer, as well as a reduction in the photodiode dark current. Thus, at $U$ = -0.2 V, the minimum dark current is $I_d$ = 200 $\mu$A for an open bridge and $I_d$ = 1 $\mu$A for devices with full insulation. Suppression of metal-assisted etching enables the fabrication of bridge-type devices on any A$^{\mathrm{III}}$B$^{\mathrm{V}}$, regardless of the material, etchant, or crystallographic orientation of the structure.
Fulltext:
PDF file (1128 kB)