A method of manufacturing a photodetector array circuit device for a mobile device, the method comprising:
- forming a compound semiconductor (CS) buffer material overlying a surface region of a silicon (Si) substrate using heteroepitaxy to nucleate the CS buffer material and to trap or filter defects;
- wherein the CS buffer material is characterized by a first bandgap characteristic, a first thermal characteristic, a first polarity, and a first crystalline characteristic;
- and wherein the silicon substrate is characterized by a second bandgap characteristic, a second thermal characteristic, a second polarity, and a second crystalline characteristic;
- forming an n-type CS material overlying the CS buffer material using heteroepitaxy, wherein the n-type material includes an InP material comprising a silicon impurity having a concentration ranging from 3E17 cm−3 to 5E18 cm−3;
- forming a CS absorption material overlying the n-type CS material using heteroepitaxy, wherein the absorption material includes an InGaAs containing material, the absorption material being primarily free from any impurity;
- forming a CS material overlying the CS absorption material using heteroepitaxy without intentional impurity;
- forming a plurality of p-type materials within portions of the CS material resulting in a plurality of photodetectors, wherein the p-type material includes a zinc impurity or a beryllium impurity having a concentration ranging from 3E17 cm−3 to 5E18 cm−3;
- wherein the plurality of photodetectors is configured in an array characterized by N and M pixel elements, where N is an integer greater than 7, and M is an integer greater than 0;
- and wherein each of the pixel elements having a characteristic length ranging from 0.3 micrometers to 30 micrometers;
- forming a plurality of isolation trenches within the CS material, the CS absorption material, and the n-type CS material, wherein the plurality of isolation trenches separate each of the photodetectors in the array;
- forming a dielectric material within the one or more isolation trenches;
- forming a first electrode coupled to the n-type CS material for each photodetector;
- forming a second electrode coupled to the p-type material for each photodetector;
- forming a first terminal coupled to the first electrode for each photodetector;
- forming a second terminal coupled to the second electrode for each photodetector to define each photodetector as a two terminal device and the plurality of photodetectors being configured as the photodetector array circuit device, wherein the photodetector array circuit device is characterized by a responsivity (Amperes/Watt) greater than 0.1 Amperes/Watt and a photodiode quantum efficiency greater than 10%;
- coupling a readout integrated circuit (ROIC) device to the photodetector array circuit device in a flip-chip bonding configuration, the ROIC device comprising a first input terminal coupled to the first terminal for each photodetector;
- a second input terminal coupled to the second terminal for each photodetector;
- and a pixel output;
- removing a portion of the Si substrate to form an illumination region characterized by an aperture to allow photons to traverse there through to interact with the CS material and the CS absorption material to cause a generation of mobile charge carriers that produce an electric current between the first and second terminals of the photodetectors;
- spatially disposing the photodetector array circuit device within a housing of the mobile device, wherein the housing includes an exterior region and an interior region;
- wherein the exterior region includes a display portion, a sensing portion, and a detecting portion;
- and wherein the photodetector array circuit device is spatially disposed such that the aperture of the illumination region configured on the detecting portion;
- and
- spatially disposing a laser device within the housing of the mobile device, wherein the laser device is configured to emit electromagnetic radiation 850 to 1550 nm wavelength range and including an aperture configured on the sensing portion.