Simultaneous High-Speed Electronic and Photonic Characterization of GaN Resonant-Tunneling Structures
Abstract
ABSTRACT:Ohio State University (OSU), in conjunction with Wright State University (WSU) proposes a DURIP equipment proposal to advance a new class of gallium nitride-based efficient and stable devices for oscillator circuits based upon quantum tunneling. First of all, we will continue to develop state-of-art nitride-based resonant tunneling diodes (RTD). Through our research and development of GaN-based RTDs on the current ONR MURI Program extension, we have demonstrated NDR-based 10-90% switching times in the range of ~50-70 ps. To the best of our knowledge, this is the first switching time measurement on GaNRTD devices ever done, and the switching speed measured is the fastest obtained so far. This means the perspective speed of GaN RTDs may be eventually comparable to InGaAs RTDs (<~20ps).Next we will explore a class of nitride RTD based, large-signal integrated-circuit components, including (transmission-line) relaxation oscillators (ROs). The ROs have been studied in the past and shown to produce RF output power exceeding 1 mW, as expected, but their maximum(repetition) frequency of oscillation has only been 50 GHz, well below the 1/4td expectation (td being the transmission-line propagation delay). A key aim of this project is working with Wright State University (WSU) for RF measurements to develop and mature a new type of stable GaNRTD-based ???relaxation??? oscillator that addresses the RTD stability issues by oscillating beyond the negative differential resistance (NDR) region.Advances by this team, leveraging the first report of the experimental determination of the quantum-well lifetime influence upon the large-signal RTD switching time [APL, 107, 153506 (2015)], our team now is poised to advance compact oscillator circuits on GaN substrates with high conversion efficiencies, generating large and stable output powers.Additionally, this also leverages this team???s first report of highly repeatable robust room temperature NDR in GaN-based RTDs [APL, 109, 083504 (2016)]. And GaN-based RTDs will enhance oscillator operation and output power by leveraging the large band offsets in the GaN based system and the large ??V between the RTD peak voltage and valley voltage, compared with their InP-based RTD counterparts.DURIP Request: To that end, we request here in this DURIP proposal: (1) a high-speed real-time oscilloscope; (2) an RF probe upgrade to an existing cryogenic probe station; (3) a high-speed pulse generator; and (4) an optical integrating sphere. The role of hole generation, which leads to some light output, will be used as a guide to engineer the GaN-based RTDs for high-speed electron-only operation.With the requested equipment, we will be able to combine DC, switching time, optical emission, temperature dependence and shot-noise characterization together, and compare all possible experimental data we can get with empirical modeling and Silvaco numerical simulation to gain deep understanding of all the transport and dynamic processes within GaN RTDs. By doing so,we target to design and fabricate a new generation of nitride-based RTDs, and then implement them for high speed, high power RF integrated circuits.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 10, 2018
- Source ID
- N000141812372
Entities
People
- Paul R. Berger
Organizations
- Office of Naval Research
- Ohio State University
- United States Navy