This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
The objective of this research is to develop a process which integrates high performance thin film silicon circuitry with compound semiconductor devices, and to use this process to demonstrate an active matrix light emitting diode capable of projecting a video brightness image. The approach is to start with high quality compound semiconductor wafers, and then deposit and recrystallize the silicon circuitry using low temperature deposition and a laser annealing process known as sequential lateral solidification. This process produces thin film silicon transistors with high mobility and minimal thermal load to the substrate.
Compound semiconductor materials are favored for a number of optoelectronic applications including photodetectors for visible, IR, and UV; light emitting diodes; and lasers. The materials used in these applications, however, generally do not form transistors and cannot be used for switching or local amplification. The approach presented in this proposal reverses the usual heteroepitaxy strategy, in which compound semiconductors are grown on a silicon wafer, and instead fabricates silicon devices on a compound semiconductor wafer. This allows integration of high quality compound semiconductor materials with silicon circuitry for switching and amplification, avoiding the limitations of other approaches.
The technology developed has a range of applications including energy efficient displays, lithography, hyperspectral detection, communication systems, and miniature biological sensors. In addition to training a graduate student, the program will mentor a high school student and an undergraduate working on the project. Light emitting diode wafer materials will be used for high school demonstrations and a course on display devices.