PHOTODETECTOR WITH INTEGRATED TEMPERATURE CONTROL ELEMENT
A temperature-controlled photodetector sub-system is described. The temperature control element allows the operation of the photodetector at a desired temperature. The temperature control element can be a heater or a cooler. In some cases, the photodetector is a germanium photodetector. In some cases a temperature measuring device is provided. In some cases, a control circuit is used to control the temperature of the germanium photodetector within a temperature range, or at a temperature of interest. An advantage provided by the apparatus described is the operation of the photodetector so that the responsivity of the germanium detector can be held at essentially a constant value.
1 - 28 . (canceled)
29 . A photonic device comprising:
a wafer comprising a waveguiding layer;
a photodetector integrated with the wafer in optical communication with the waveguiding layer; and
a temperature control element integrated with the wafer proximate to the photodetector so as to control the temperature thereof.
30 . The photonic device of claim 29 , wherein the photodetector is a germanium photodetector.
31 . The photonic device of claim 29 , wherein the temperature control element comprises one of a heater and a cooler.
32 . The photonic device of claim 29 , wherein the temperature control element is disposed at most 10 microns apart from the photodetector.
33 . The photonic device of claim 29 , wherein the temperature control element is disposed less than 50 microns apart from the photodetector.
34 . The photonic device of claim 29 , wherein the temperature control comprises a Peltier device.
35 . The photonic device of claim 29 , further comprising a thermal measurement device situated proximate to the photodetector.
36 . The photonic device of claim 35 , including a control circuit connecting the temperature control element with the thermal measurement device and configured to control a temperature of the photodetector in a predetermined temperature range.
37 . The photonic device of claim 29 , wherein the temperature control element comprises two heaters disposed on opposite sides of the photodetector or two coolers disposed on opposite sides of the photodetector.
38 . The photonic device of claim 29 , wherein the waveguiding layer comprises a semiconductor.
39 . The photonic device of claim 29 , wherein the temperature control element comprises a resistive heater.
40 . The photonic device of claim 29 further comprising an electrical signal barrier disposed between the photodetector and the temperature control element.
41 . The photonic device of claim 40 , wherein the electrical signal barrier comprises a p-n-p-n junction.
42 . A method of operating a photonic device in a predefined wavelength range across a first temperature range, the photonic device comprising a wafer and a photodetector integrated therewith, the photodetector being capable of efficiently detecting light of the predefined wavelength range within only a portion of the first temperature range, the method comprising:
integrating a temperature control element with the wafer proximate to the photodetector, and
operating the temperature control element to maintain a temperature of the photodetector within the pre-determined portion of the first temperature range.
43 . The method of claim 42 , comprising using a germanium photodetector as the photodetector.
44 . The method of claim 42 , comprising using one of a heater and a cooler as the temperature control element.
45 . The method of claim 42 , comprising integrating the temperature control element at most 10 microns away from the photodetector.
46 . The method claim 42 , wherein the photodetector is disposed on a semiconductor layer, and wherein the integrating the temperature control element comprises forming the temperature control element at least in part in the semiconductor layer or over the semiconductor layer.
47 . The method claim 46 , comprises forming an electrical signal barrier in the semiconductor layer between the temperature control element and the photodetector.
48 . The method of claim 42 , wherein integrating the temperature control element comprises integrating a heater proximate to the photodetector.