Design and manufacture of a test crystal for detection of specific radiation types


  • Optoelektronik
Detection of radiation particles and making their video image are an important part of a wide range of scientific problems and practical applications. This is physics of elementary particles, astrophysics, defect detection, customs supervision and so on.

For this purpose at present traditional semiconductor devices are applied, namely, charge-coupled devices (CCD), avalanche photodiodes (APD), microstrip detectors and so on.

However, the rapid growth of microelectronics during the recent years as well as new, first of all, Russian inventions can sharply change the situation in this field and, what is most important, to broaden essentially the field of application of radiation detectors. In this connection the main goal of the project is the creation of a new generation of extensively applied coordinate-sensitive detectors with radically better features on the basis of our elaborations and inventions.

The project supposes to design and manufacture a test crystal containing various functionally integrated pixel structures optimized for detection of specific radiation types. In particular, a hybrid of the p-i-n diode and bipolar transistor is effective for high-speed amplitude registration of heavy charged particles. Such a construction of the detector will make it possible to provide the amplification of primary signal without external off-chip or stationary amplifiers. To minimize barrier capacities, the emitter and base-range diameters must be as small as 3-5 and 6-8 mm, respectively. When using the detector construction proposed for the first time in the world, it is planned to get the following characteristics: the time of information signal selection is less than 10 ns; the coordinate resolution is better than 10?10 mm2; the sensitivity is one (or more) order of magnitude higher than that of usual or microstrip detectors.

The authors intend to achieve the above-mentioned goals by using the most perfect silicon technologies, namely, silicon-on-insulator (SOI), and application of so-called functionally integrated structures. The absence of external amplifiers and realization of new-type detectors on the basis of present-day silicon technologies of production of Very Large-Scale Integrated (VLSI) circuits reduces sharply the cost of all the detecting system.

Radical improvement of detector features make it possible to extend sharply the range of their application, namely, from the solution of specific problems of radiation physics to practical applications of medicine radiography, customs supervision, defect detection and so on. So, the main goal of this project is as follows: elaboration, production and market sale of multipurpose new-generation pixel coordinate-sensitive detector based on functionally integrated structures. The project includes also the use of pixel functionally-integrated detector to design social and special-purpose dosimeters; coordinate detectors for the radiometer's detecting unit, coordinate matrix for medicine X-ray diagnostic apparatuses.

The expected profit of sales of matrix pixel functionally-integrated coordinate-sensitive detectors will be several hundred times higher than the inputs for technology elaboration and organization of their production.