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© 1990-2002 J.Paul Robinson,
Purdue University BMS 631 –
LECTURE007.PPT
Silicon
photodiodes
•A silicon photodiode produces current when photons impinge upon it (example are solar cells)
•Does not require an external power source to
operate
•Peak sensitivity is about 900 nm
•At 900 nm the
responsivity is about 0.5 amperes/watt, at 500 nm it is 0.28 A/W
•Are usually operated in the photovoltaic mode (no external
voltage) (alternative is photoconductive
mode with a bias voltage)
•Have no gain so must have external amps
•quantum efficiency (f)% = 100 x (electrons out/(photons in)
