University of Delaware

Paul R Berger

Wei Gao

Karl D Hobart

Phillip E Thompson

Sean L Rommel

Roger Lake

Interband tunnel diodes which are compatible with Si-based processes such as, but not limited to, CMOS and SiGe HBT fabrication. Interband tunnel diodes are disclosed (i) with spacer layers surrounding a tunnel barrier; (ii) with a quantum well adjacent to, but not necessarily in contact with, one of the injectors, and (iii) with a first quantum well adjacent to, but not necessarily in contact with, the bottom injector and a second quantum well adjacent to, but not necessarily in contact with, the top injector. Process parameters include temperature process for growth, deposition or conversion of the tunnel diode and subsequent thermal cycling which to improve device benchmarks such as peak current density and the peak-to-valley current ratio.

Si-based resonant interband tunneling diodes and method of making interband tunneling diodes

A metal-semiconductor-metal (MSM) photodetector, specifically a new, improved low noise device is disclosed. The disclosed device is a MSM photodiode in which the cathode and anode are made of different materials with optimal Schottky barrier heights. One of these materials is chosen to provide a high ratio of Schottky barrier height to hole transport and the other to provide a high ratio of Schottky barrier height to electron transport. The disclosed MSM photodetector is designed to allow each Schottky barrier to be individually optimized to the point that a wide bandgap Schottky barrier enhancement layer and its associated heterointerface may become unnecessary. Elimination of the charge buildup at the heterointerface enhances carrier extraction resulting in photodetectors with elevated quantum efficiency and enhanced bandwidths.

Asymmetric contacted metal-semiconductor-metal photodetectors

An improved metal-semiconductor-metal (MSM) photodiode, specifically a new high responsivity AND high bandwidth photodetector, resulting in a high gain-bandwidth product is disclosed. The disclosed device is an MSM photodiode in which the anode and cathode are made of different materials of differing opacity and possibly including different electrode dimensions as well. Using an opaque anode and a transparent cathode reduces surface reflections off the opaque electrodes allowing more light to be absorbed within the active semiconductor region. However, it concurrently keeps the transit distance for the slower moving holes to a minimum. Thus, the long tail in the impulse response due to hole collection is minimized, resulting in increased bandwidth.

Growing community of inventors

Newark, DE, United States of America

Paul R Berger