Introduction
To begin with, We have chosen this topic due to the fact that silicon radiation detectors are one of the main type of particle detectors used in the radiation detection industry nowadays. Hence, it is crucial for an engineer in this field to know the history of silicon production as well as the development process and concrete examples of the different types of detectors.
In this wiki page we are studying the rapid progress of the silicon radiation detectors, the design of the single sided stereo angle silicon strip detector and the development of the detectors in the VTT Technical Research Centre of Finland. The information was collected from Institute of Electrical and Electronics Engineers/Institution of Electrical Engineers (IEEE/IEE) Electronic Library online.
History of silicon radiation detectors
According to Rehak (2003), silicon is the main material which is used in electronics and radiation detection industries. Moreover, there was a rapid development in the field of silicon radiation detectors in the last decade, which could be noted as a considerable progress after 1982, when planar technology was invented. [1.] Furthermore, according to Orava et al (2007), even today new development activity is initiated with introduction of 3D detector technologies, active edge silicon processing and other perspective inventions in the field. [3.] It has to be said that there is always interaction between electronics industry and silicon radiation detectors because they both use silicon as the main component. The main point is that silicon used for radiation detectors should have 3-4 times more resistivity and lower density of traps than the one used for electronics. [1.]
Interestingly, almost all radiation detectors before 1982 were lithium-drifted (Figure 1). Lithium doping was used in order to increase the thickness of the detector and thus to decrease the capacitance and apply reasonable voltages which would lead to lower noise levels.
Figure 1. Lithium drifted silicon detector. Reprinted from Rehak (2003) [1,2494].
However, the main disadvantage was the instability of the surfaces along the field of the detector and working temperature of about 77K. Obviously, silicon radiation detectors which could be used at room temperature were drastically needed. [1.]
Planar technology was introduced in 1982, which led to the rapid progress in development of the silicon detectors. Among others, strip detectors were invented and matched to meet the requirements of the Large Hadron Collider (LHC) developed at The European Organization for Nuclear Research (CERN). Main advantages were lower noise, smaller capacitance, room working temperature, easier production, reduced cooling requirements and larger area coverage. [1;3]