Invention combines wafer-scale optical devices onto a chip used in telecommunications
A new invention by UCF researchers provides the telecommunications industry with a low-cost way to combine optical devices such as high-speed detectors, modulators, and low-noise lasers onto a compact, stable integrated chip. The new photonics platform operates over octave-spanning or multi-octave spectral windows. Researchers developed the platform using a unique, repeatable manufacturing method that produces wafer-scale photonic systems with extremely low propagation losses and a wide transparency window. The invention greatly improves the thermal management of compact optical devices and reduces power consumption needs, resulting in longer lifetimes, higher speeds, and lower cost-of-ownership.
The platform consists of a novel semiconductor quantum heterostructure in a suspended thin film ("membrane") that enables the construction of efficient and high-speed optical devices. To produce the platform, manufacturers can implement various approaches, as shown in the following examples. Manufacturers can use different materials and combinations of materials to suit different application sectors and wavelength requirements.
Example 1: This method uses a donor substrate to epitaxially grow a quantum heterostructure on a planar semiconductor membrane (the active layer). The active layer is transferred from the donor substrate and bonded onto a new substrate that is pre-patterned with one or more trenches. The donor wafer has an “etch-stop” layer that enables precise removal of the backside etch, leaving only the desired thin membrane with the heterostructure.
Example 2: This method bonds a donor substrate onto a pre-patterned substrate. The substrate is then thermally sliced to form a seed layer for epitaxially growing the quantum heterostructure.
Besides different processing methods, the invention enables many geometric arrangements for the mode of a platform’s optical waveguide structures. In Example 3 (a), the platform has an etched ridge that confines the optical mode. In example (b), the platform has a “post” that confines the optical mode.
Sketches for the above examples are available in the online image gallery for this tech sheet.
- Scalable, simple, reliable and easily repeatable low-cost manufacturing method
- Boosts performance in harsh environments and provides greatly improved thermal management
- Reduces power consumption and increases operational lifetimes
- Integrated lasers, modulators or high-speed optical detectors that operate in the 1.55 µm wavelength