Component for light detection and emission

Claim 2

A solid-state light emitter and receiver component comprising superimposed upon one and the same substrate an electroluminescent diode and a photodiode, said electroluminescent diode and said photodiode operating respectively in a first and in a second light frequency band, said electroluminescent diode being transparent vis-a-vis said second light frequency band, and means for alternately rendering said electroluminescent conducting and said photodiode blocked.

Claim 3

A component as claimed in claim 1 said electroluminescent diode and said photodiode comprising respectively a first and a second junction, and first, second and third metal contacts respectively upon said substrate and said first and second junctions.

Claim 4

A component as claimed in claim 2 wherein said first and second junctions are conductive when voltages of the same polarity are applied thereupon.

Claim 5

A component as claimed in claim 2 said first and second junctions are conductive and blocked respectively for voltages of same polarities applied thereupon.

Claim 6

A component as claimed in claim 4, comprising superimposed upon one and the same substrate of a first conductivity type, a first layer of said same conductivity type, a second layer of a second conductivity type which is the opposite to the first, a third layer of the first conductivity type and a fourth layer of the first conductivity type.

Claim 7

A component as claimed in claim 5, wherein the first conductivity type is p type and the second n type.

Claim 8

A component as claimed in claim 6, wherein said first layer is weakly doped and, with said substrate and said second layer, forms a PIN photodiode, the first layer being absorbing in said frequency band.

Claim 9

A component as claimed in claim 7, wherein said third layer is weakly doped and forms the source of light emission of said electroluminescent diode.

Claim 10

A component as claimed in claim 8, wherein said substrate is made of gallium-arsenide with a doping level at least equal to 10 18 At/cm 3 , said first layer has a thickness of 1 to 3 microns and a doping level of less than 10 17 At/cm 3 , said second layer has a doping level greater than 10 18 At/cm 3 and a thickness of 1 to 10 microns with a composition corresponding to the formula Ga Al x As.sub. 1 - x where x at least equal to 0.2, said third layer has germanium doping and a thickness of the order of 0.1 to 1 microns, its composition satisfying the formula Ga.sub. 1 - y Al y As, where y substantially equal to 0.1, and the fourth layer has the same composition as the second, and a thickness of 1 to 10 microns.

Claim 11

A component as claimed in claim 9, wherein said electrical contacts are formed, the first on the substrate, the second on the second layer and the third on the fourth layer.

Claim 12

A component as claimed in claim 10, wherein said second contact is at the periphery of said second layer.

Claim 13

A component as claimed in claim 10, wherein said second contact is a deep n zone diffused across said first and fourth layers.