Tetra-lateral position sensing detector

A position sensing detector comprising a photodiode having an active area with a first corner, a second corner, a third corner, and a fourth corner, said photodiode comprising

• a buffered layer formed directly atop a substrate layer,
• four-cathode electrodes electrically coupled to said buffered layer, wherein a first of said four cathode electrodes is positioned in the first corner, a second of said four cathode electrodes is positioned in the second corner, a third of said four cathode electrodes is positioned in the third corner, and a fourth of said four cathode electrodes is positioned in the fourth corner;
• and
• at least one anode electrode electrically coupled to a p-type region, wherein said detector is capable of detecting eye-safe wavelengths.

A position sensing detector comprising a photodiode having an active area, said photodiode being defined by a first corner, a second corner, a third corner, and a fourth corner and comprising

• a substrate layer;
• a buffered layer, wherein said buffered layer is formed atop the substrate layer;
• an absorption layer, wherein said absorption layer is formed atop the buffered layer;
• a cap layer with a p-type region, wherein said cap layer is formed atop the absorption layer, wherein a p-n junction is formed between said cap layer and said absorption layer;
• four cathode electrodes electrically coupled to said buffered layer, wherein a first of said four cathode electrodes is positioned in the first corner, a second of said four cathode electrodes is positioned in the second corner, a third of said four cathode electrodes is positioned in the third corner, and a fourth of said four cathode electrodes is positioned in the fourth corner;
• and
• at least one anode electrode electrically coupled to said cap layer, wherein said p-type region is doped with an effective amount of metal to achieve a predefined position detection error across the active area.