Patent ID: 7608830

Claim:
A multicolor photodetection structure, comprising: a monolithic semiconductor heterostructure defining a photodiode, the photodiode comprising first and second photoabsorption regions of two different bandgaps and an N+ region formed on the first photoabsorption region, the first photoabsorption region having a first conductivity type and the second photoabsorption region having a second conductivity type; a first contact electrically connected to the N+ region; a backside contact electrically connected to the second photoabsorption region; and circuitry electrically connected to the N+contact region via the first contact and electrically connected to the second photoabsorption region via the backside contact, wherein the circuitry: in a first mode, biases, via only the first contact and the backside contact, both said photoabsorption regions to collect photocarriers therefrom, without forward bias on either; and in a second mode, biases, via only the first contact and the backside contact, only one of said photoabsorption regions to collect photocarriers therefrom, without forward bias on either.