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GaAs photodiode (PD)

Two or three-inch epiwafers grown by MOVPE are available for GaAs photodiode (PD) fabrication.  The GaAs PD is widely used in the Gigabit Ethernet receiver or transceiver where laser’s wavelength is shorter than 870nm.

 

Epitaxial Capability

 Parameters  Values
 Thickness control  Better than ±5%
 Thickness uniformity  Better than ±2% at the inner 40mm
 PL Wavelength uniformity  ~870nm, no variation is observed
 Doping control  ~±20% for P-type ; ~±20% for N-type
 Zn diffused P-InGaP  (cm-3)  Zn doped; 1E17 to 3E18
 N-GaAs doping  (cm-3)  Si doped; 5E17 to 5E18
 P-AlGaAs doping  (cm-3)  C doped; >1E18
 U-InGaP background C.C (cm-3)  5E15~2E16
 I-GaAs background C.C. (cm-3)  <5E14; Minimum ~8E13
 Defect density control (Diameter)  <50cm-3(D>10μm)

 

Device Performance

 Parameter  Symbol  Typical
 Dark Current @-5V

Id

  <100pA
 Capacitance @-5V

CP

  ~0.65pF
 Responsivity

Res

  ~0.65 A/W (@850nm)
 Break down Voltage @10μA

VR

  >20V
 Serial resistance

Rs

  <50Ω
 Good device yield —  >80%
 Zn diffused, planar type PIN

100 μm aperture