Patent ID: 11881490
Assignee: AELUMA, INC.
Field: Semiconductors (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 31:
32. A method of assembling a photodetector module device, the method comprising:
providing a module housing, having an exterior region and an interior region, the exterior region having an emitting aperture and a sensing aperture;
spatially disposing a laser device coupled to the emitting aperture and configured to emit electromagnetic radiation having 850 to 1550 nm wavelength range; and
spatially disposing a photodetector circuit coupled to the sensing aperture, the circuit comprising:
a first terminal;
a second terminal;
a silicon (Si) substrate comprising a surface region, the silicon substrate being a portion of a large silicon substrate having a diameter ranging from 4 inches to 12 inches in size;
a plurality of v-grooves having a feature size of 50 to 500 nm in width, each of the v-grooves exposing a 111 crystalline plane of the Si substrate;
a nucleation layer comprising a gallium arsenide material to coat the surface region of the Si substrate, the nucleation layer having a thickness ranging from 10 nm to 100 nm;
a buffer material comprising a plurality of nanowires formed overlying each of the plurality of v-grooves and extending along a length of each of the v-grooves, a first transitionary region extending from each of the plurality of nanowires, and a second transitionary region characterized by a 100 crystalline planar growth of a gallium arsenide compound semiconductor (CS) material configured using a direct heteroepitaxy such that the CS material is characterized by a first bandgap characteristic, a first thermal characteristic, a first polarity, and a first crystalline characteristic, and the silicon substrate is characterized by a second bandgap characteristic, a second thermal characteristic, a second polarity, and a second crystalline characteristic;
an array of photodetectors, the array being characterized by N and M pixel elements, where N is an integer greater than 7, and M is an integer greater than 0; each of the pixel elements having a characteristic length ranging from 0.3 micrometers to 30 micrometers, each of the photodetectors comprising:
an n-type material comprising an InP material comprising a silicon impurity having a concentration ranging from 3E17 cm-3 to 5E18 cm-3 overlying the buffer material;
an absorption material overlying the n-type material, the absorption material comprising an InGaAs containing material, the absorption material being primarily free from any impurity;
a p-type material overlying the absorption material, the p-type material comprising a zinc impurity or a beryllium impurity having a concentration ranging from 3E17 cm-3 to 5E18 cm-3;
a first electrode coupled to the n-type material and coupled to the first terminal;
a second electrode coupled to the p-type material and coupled to the second terminal to define a two terminal device;
an illumination region characterized by an aperture region to allow a plurality of photons to interact with the CS material and be absorbed by a portion of the absorption material to cause a generation of mobile charge carriers that produce an electric current between the first terminal and the second terminal;
a responsivity (Amperes/Watt) greater than 0.1 Amperes/Watt characterizing the circuit between the first terminal and the second terminal according to the following equation:, R
  =
  
   η
   ⁢
   
    q
    
     h
     ⁢
     v, where η is the internal quantum efficiency, q is the electron charge, h is Planck's constant, and v is the photon frequency; and
a photodiode quantum efficiency greater than 10% characterizing the circuit as measured between the first terminal and the second terminal according to the following equation: QE=1240×(Rλ/λ) where Rλ is responsivity in A/W and λ is wavelength in nm;
wherein each photodetector is configured with a separate absorption material comprising InGaAs or InGaAsP, and a multiplication material comprising InP whereby the multiplication material generates additional charge carriers by avalanche gain.