Silicon tracking detectors—historical overview

Abstract

Semiconductor detectors have been known for more than 50 years, however their tracking capabilities, exhibiting spatial resolution in the 5–10 μm range, began to be explored only in the beginning of the 1980s, when experimental physics began to search for detectors to measure short-living particles. The introduction of planar technology provided a boost to the industrial production and use of silicon strip detectors. The next essential step came with the development of a dedicated VLSI readout, which allowed for integration of detectors and electronics. Efforts towards obtaining two-dimensional detectors were initiated right from the beginning, with CCD devices being the subject of early investigation. A second line of development involved pixel devices with thick sensitive layers—they began to be successfully implemented in experiments towards the end of the 1990s. Radiation effects in detectors and electronics were recognized early, however it took many years to understand the physics of radiation damage—currently, we possess detectors and electronics capable of surviving doses of 10 Mrad and fluxes of 10 14 neutrons/cm 2, or higher. Nowadays, all particle physics spectrometers have inbuilt vertex detectors, which deliver excellent results. The application of silicon tracking detectors has expanded to nuclear physics, solid-state physics, astrophysics, biology and medicine.