Light emitting and light detecting semiconductor device for interfacing with an optical fiber

Claim 1

A light emitting and light detecting semiconductor device having a light emitting zone and a light detecting zone adaptable for concurrently interfacing with an optical fiber, comprising: a primary region of a first conductivity type; the light detecting and light emitting zones being of a second conductivity type extending into the primary region from a first surface of the primary region, the zones being separated from each other by a separation region, a junction being formed at an interface between each zone and the primary region, the zones having a depth measured from the first surface; and a separation material different from the material of the primary region, the separation material extending into at least a portion of the separation region from the first surface to a depth greater than the depth of either zone, the separation material providing substantial optical isolation between the two zones.

Claim 20

A device as in claims 1 or 2 further comprising the optical fiber having a port located in proximity to the light detecting and light emitting zones such that at least a portion of any light at the port is received by the light detecting zone and at least a portion of any light emitted by the light emitting zone is received by the port for transmission over the optical fiber.

Claim 21

A device as in claims 1, 2, or 5 further comprising positioning means connected to the device, the positioning means being adapted for positioning a port of an optical fiber in proximity to the light detecting and light emitting zones.

Claim 22

A device as in claims 1, 2, or 5 further including an electrical circuit, comprising: an input terminal for receiving input signals having first and second levels; means comprising control means connected between the input terminal and the light emitting zone for permitting the application of a positive voltage to the light emitting zone whenever the first signal level is present at the input terminal; a positive voltage terminal adapted to receive the positive voltage; means connecting the positive voltage terminal to the control means; a negative voltage terminal adapted to receive a negative voltage; means connecting the negative voltage terminal to the light detecting zone; an output terminal; and means connecting the output terminal to the light detecting zone for providing a signal at the output terminal whenever light is received by the light detecting zone while the junction between the light detecting zone and the primary region is reverse biased.

Claim 23

A device as in claims 1, 2, or 5 further including an electrical circuit, comprising: an input terminal for receiving input signals having first and second signal levels; a positive voltage terminal adapted to receive a positive voltage; a negative voltage terminal adapted to receive a negative voltage; means connecting the negative voltage terminal to the light detecting zone; inverter means for converting logic highs to logic lows and vice versa, the inverter means having an input connected to the input terminal, the inverter means also having an output; control means comprising a transistor with a base connected to the output of the inverter means, an emitter adapted for connection to a reference potential, and a collector; means connecting the collector of the transistor to the light emitting zone; means connecting the collector of the transistor to the positive voltage terminal; an amplifier having an input and an output; means connecting the input of the amplifier to the light detecting zone; an output terminal; means connecting the output terminal to the output of the amplifier; and means adaptable for connecting the primary region to the reference potential.