Methods and apparatus providing thermal isolation of photonic devices

#Described embodiments relate generally to the field of electronic-photonic devices, and more particularly to the thermal isolation of electronic-photonic devices.

#Optical transmission may be used as a means for communication between separate integrated circuit die (also referred to as inter-die connections), and between components on the same die (also referred to as intra-die connections). Photonic devices are a class of devices that are capable of sourcing, controlling, and/or detecting optical transmission of signals.

#The term “silicon photonics” relates to the study and application of photonic systems-that use silicon as an optical medium. Instead of, or in addition to, using silicon to facilitate the flow of electricity, silicon can be used to direct the flow of photons or light. Silicon is transparent to infrared light with wavelengths above about 1.1 micrometers. Silicon also has a high refractive index of about 3.5. The tight optical confinement provided by this high index allows for microscopic optical waveguides, which may have cross-sectional dimensions of only a few hundred nanometers, thus facilitating integration with current nano-scale semiconductor technologies that also employ silicon, such as complementary metal oxide semiconductor (CMOS) technologies. Silicon photonic devices can thus be made using existing semiconductor fabrication techniques. Further, because silicon is already used as a substrate for many electronic integrated circuits, it is possible to create hybrid devices employing both optical and electronic components integrated onto a single die.

#FIG. 1 illustrates a block diagram of a conventional photonic system.

#FIGS. 2A and 2B illustrate a top-down view and a cross-sectional view, respectively, of photonic devices in a die.

#FIGS. 3A-3E illustrate a top-down view and cross-sectional views, respectively, of die including thermal isolation regions, in accordance with embodiments described herein.

#In the following detailed description, reference is made to various embodiments. These embodiments are described with sufficient detail to enable those skilled in the art to practice them. It is to be understood that other embodiments may be employed, and that various structural, logical and electrical changes may be made. In addition, where various processes are described, it should be understood that the steps of the processes may occur in an order other than how they are specifically described, unless noted otherwise.

#Embodiments described herein include photonics devices and integrated circuits with a thermal isolation region for controlling dissipation of heat in a photonic system. For example, a thermal isolation region may be formed near one or more temperature-sensitive photonic structures.

#FIGS. 3A and 3B illustrate one embodiment. They show a top-down view and a cross-sectional view, respectively, of photonic devices formed in a portion of a die 330. As shown in FIG. 3A, die 330 may include one or more temperature sensitive photonic devices of a photonic system, including, for example, a resonant carrier wave modulator 320, such as a ring resonator or disk resonator, or another type of resonant modulator. Carrier wave modulator 320 may be an electro-optical modulator configured to receive an electrical data signal from an electrically connected interconnect, such as an electrically conductive signal line, and modulate a carrier wave in an adjacent optical waveguide 315 according to the received data. Alternatively, carrier wave modulator 320 may be an optical modulator configured to receive an optical data signal, such as from another optical waveguide.