Compact, Low-Cost THz Test System

ABSTRACT: In this Phase I STTR project, we propose to demonstrate the feasibility of developing a low cost, compact, time-domain terahertz (TD-THz) spectrometer specifically for the characterization of semiconductor materials over a range of temperatures, electric fields, and magnetic fields. In phase I, we will configure fiber optic coupled TD-THz instrumentation to make measurements on a sample using a commercial, off the shelf (COTS) optical cryostat and with variable electrical and magnetic field. We will specify analysis methods to determine relevant semiconductor parameters such as doping concentrations and carrier mobility from the THz spectral data. We will demonstrate these methods by collecting and analyzing the THz spectra of representative semiconductor samples as a function of temperature, electric field and magnetic field. In this Phase I STTR project, we propose to demonstrate the feasibility of developing a low cost, compact, time-domain terahertz (TD-THz) spectrometer specifically for the characterization of semiconductor materials over a range of temperatures, electric fields, and magnetic fields. In phase I, we will configure fiber optic coupled TD-THz instrumentation to make measurements on representative semiconductor samples using a commercial, off the shelf (COTS) optical cryostat and with variable electrical and magnetic field. We will specify analysis methods to determine relevant semiconductor parameters such as doping concentrations and carrier mobility from the THz spectral data. We will demonstrate these methods by collecting and analyzing the THz spectra of representative semiconductor samples as a function of temperature, electric field and magnetic field. We will develop the specifications for a Phase II prototype TD-THz test system using fiber optic coupled THz instrumentation and components for automatically acquiring the THz spectral data under the relevant conditions. The fiber optic THz transmit and receive modules would be integrated into a sample cryostat with variable electric and magnetic field.rade offs in features, size, weight, and cost will be discussed. BENEFIT: Upon successful completion of the Phase II project, the proposed TD-THz spectrometer will provide a turn-key system for the determination of semiconductor electronic and optical properties such as doping concentration and carrier mobility. The instrument will acquire TD-THz spectra from 0.1 to>3THz. The sample under test may be measured at a wide range of cryogenic temperatures, electric fields, and magnetic fields. The instrument will employ software which automates the Phase I algorithms to calculate the electronic and optical parameters of the semiconductor samples. The instrument will be suitable THz spectroscopy of pharmaceuticals, synthesized organic compounds, explosives, and other material.