Doping profile measurement using terahertz time domain spectroscopy (THz-TDS)

摘要

A system and method for determining a doping profile of a sample includes a generator and at least one detector of terahertz light of multiple frequencies, configured to operate in a transmission and/or reflection mode; a materials refractive index library; and an inverse algorithm that can match simulated spectra using a trial doping profile and the materials library with the measured spectra from a sample, and map out or measure an activated doping profile into, or a free carrier distribution into, the interior of the sample.

主权项

1. A system for determining a doping profile of a sample comprising:
a generator of terahertz light of multiple frequencies; a first detector of terahertz light of multiple frequencies, wherein the generator and first detector are configured to operate in a transmission or reflection mode with respect to independently exposing both a sample of unknown doping profile and an undoped reference sample to terahertz frequency radiation traveling through the unknown sample and through the reference sample and detecting a measured spectra of terahertz frequency for each of the unknown sample and the reference sample; a materials refractive index library comprising a database comprising multiple doping concentrations of a dopant for a base material and at each of the multiple doping concentrations a refractive index and absorption coefficient at each of different wavelengths; and a processor comprising an inverse algorithm that can match simulated spectra using a trial doping profile and the materials library with the measured spectra from the sample, and map out or measure an activated doping profile into, or a free carrier distribution into, the interior of the sample.