Photonics IC (PIC) with Extended Operating Temperature Range
A package includes an electronic IC (EIC) coupled with a PIC at the top of the PIC. The EIC has a thermal controller, a signal interface, and a device interface. The PIC has a photonic device and a device heater. The device heater is located within 3,000 nm from the photonic device. The PIC receives heater power from the bottom of the PIC. A thermal controller in the EIC receives information of the temperature of the photonic device and controls the heater power applied to the device heater.
1 . A package comprising:
an electronic integrated circuit (EIC); and
a photonic integrated circuit (PIC) coupled with the EIC, the PIC including:
a photonic device coupled with the device interface through first electrical connections on a first side of the PIC, and
a device heater configured to receive a first input through second electrical connections connected on a first side to the device heater, the second electrical connection extending to a second side of the PIC opposite to the first side;
a temperature sensor in a region near the photonic device;
a thermal controller configured to receive a second input from the temperature sensor associated with a thermal condition in the region near the first photonic device and to obtain data associated with the current thermal condition; and
wherein the thermal controller is further configured to use the data to selectively alter a voltage that is received at the second electrical connections on the second side of the PIC by sending a signal via third electrical connections.
2 . The package of claim 1 , wherein:
the photonic device is a photodetector, and the EIC comprises an amplifier configured to receive a demodulated signal from the photodetector.
3 . The package of claim 2 , wherein the amplifier is a transimpedance amplifier (TIA).
4 . The package of claim 1 , wherein:
the photonic device is a modulator, and the EIC comprises a driver configured to forward a modulation signal to the modulator.
5 . The package of claim 1 , wherein the first input comprises heater power.
6 . The package of claim 1 , wherein the PIC send the signal via the third electrical connections to an external power source.
7 . The package of claim 1 , wherein the device heater is located proximate to the photonic device at a distance of between approximately 200 and 3,000 nanometers.
8 . The package of claim 1 , wherein the device heater includes any of tungsten, titanium nitride, copper, aluminum, another metal, doped silicon, and/or polycrystalline silicon.
9 . The package of claim 1 , wherein the device heater is shaped as a strip located above a semiconductor waveguide included in the photonic device.
10 . The package of claim 1 , wherein the photonic device includes a germanium (Ge) or germanium silicon (GeSi) waveguide in a PIN diode.
11 . The package of claim 1 , wherein the EIC comprises a serial bus.
12 . The package of claim 1 , further comprising:
a substrate coupled with the EIC and/or the PIC; wherein:
the substrate is configured to receive the first input from a heater power source and to forward the heater power to the PIC;
the PIC is configured to receive the heater power from the substrate and to forward the heater power to first device heater;
the package is configured to forward the second input from the temperature sensor to the EIC; and
the EIC is configured to receive the second input and to forward it to the thermal controller.
13 . The package of claim 12 , wherein the temperature sensor is included in the PIC and/or in the EIC.
14 . The package of claim 12 , wherein the temperature sensor is a package temperature sensor.
15 . The package of claim 12 , wherein the EIC is mounted on the PIC and the PIC is mounted on the substrate.
16 . The package of claim 12 , further comprising an interposer, and wherein the EIC is mounted on the PIC and the PIC is mounted on the interposer and the interposer is mounted on the substrate.
17 . The package of claim 16 , further comprising a processor mounted on the interposer.
18 . A method of compensating temperature effects in a photonic device in a photonic integrated circuit (PIC), comprising one or more cycles of:
in a temperature sensor, measuring a temperature in a region near the photonic device;
communicating the temperature to a thermal controller in an electronic integrated circuit (EIC);
in the thermal controller, determining if the temperature requires an action; and
based on determining that the action is required, determining a value for a power control signal, communicating the power control signal to a heater power source, changing heater power based on the power control signal, and applying the heater power to a device heater located within three thousand nanometers (3,000 nm) from the photonic device, wherein a magnitude of the power control signal is associated with the temperature.
19 . The method of claim 18 , wherein the temperature sensor is at least partially located in the PIC.
20 . The method of claim 18 , wherein the temperature sensor is located on a substrate on which the PIC is mounted.
21 . The method of claim 18 , wherein the temperature sensor is located in the EIC and the EIC is mounted on the PIC.
22 . The method of claim 18 , wherein the thermal controller includes a microcontroller.
23 . The method of claim 18 , wherein determining the value for the power control signal comprises looking up the magnitude in a table that associates the temperature with the magnitude.
24 . The method of claim 18 , wherein communicating the power control signal includes sending the power control signal over a signal bus.
25 . The method of claim 24 , wherein the PIC includes a function to bridge multiple EICs.
26 . A method of compensating temperature effects in a photonic device, comprising:
receiving temperature information;
using the temperature information for a table address to find heater power control data; and
using the heater power control data to set a heater power level.
27 . The method of claim 26 , wherein the photonic device is included in a photonic IC (PIC) that includes a function to bridge multiple electronic integrated circuits (EICs).