  Thin film detectors which incorporate semiconductor materials other than
silicon have the potential to build upon their unique material properties and
offer advantages such as faster response times, operation at room temperature,
and radiation hardness. To explore the possibility, promising candidate
materials were selected, and particle tracking detectors were fabricated. An
indium phosphide detector with a metal-insulator-metal (MIM) structure has been
fabricated for particle tracking. The detector was tested using radioactive
sources and a high energy proton beam at Fermi National Accelerator Laboratory.
In addition to its simplistic design and fabrication process, the indium
phosphide particle detector showed a very fast response time of hundreds of
picoseconds for the 120 GeV protons, which are comparable to the ultra-fast
silicon detectors. This fast-timing response is attributed to the high electron
mobility of indium phosphide. Such material properties can be leveraged to
build novel detectors with superlative performance.
