MISIS and NPCC DiT DZM: Manufacturing technology of X-ray detectors

The main articles are:

• X-Ray Equipment (Global Market)
• Halide perovskites

2023: Introduction of X-ray detector manufacturing technology

Scientists at the University of Science and Technology MISIS and the Center for Diagnostics and Telemedicine DZM have proposed technology for the manufacture of X-ray detectors used to check luggage at the airport or for computed tomography in hospitals. The University announced this on August 25, 2023.

Detectors based on perovskite material will reduce the cost of devices and increase sensitivity to X-ray radiation. The opening of their production in Russia will allow import substitution of foreign analogues.

Perovskites are a class of materials with a special crystal structure that have high efficiency in converting X-rays into electrical signals. Unlike traditional materials such as silicon and amorphous selenium, perovskite detectors have high sensitivity, low cost and ease of manufacture. However, all the development of devices based on them is at the stage of research and industrial application has not yet been achieved.

"We are developing a next-generation detector structure based on perovskite. Perovskite is a modern type of semiconductor material. It responds sensitively to ionizing radiation, which is used in radiology, by glow or electric signal. Increasing the sensitivity of shooting will reduce the radiation load on the patient. We have shown that the perovskite crystal withstands high doses of radiation without losing its optical properties, which provides a long life. We are confident that perovskites will become the basis of post-silicon electronics, "said Artur Ishteev, a researcher at the Center for Diagnostics and Telemedicine of the DZM, engineer of the solar power laboratory at NITU MISIS.

As of August 2023, researchers at the Laboratory for Advanced Solar power NUST MISIS have already obtained a prototype detector matrix with a pixel size of 50 by 50 microns (0.001 mm), and the first tests showed the effectiveness and performance of the prototype - a photocurrent passes through the detector when irradiated, and there is isolation between the pixels. At the same time, prototypes of detectors for X-ray and PET/CT devices are made on the basis of perovskite photoconverters from completely domestic materials on Russian equipment.

"Russia does not yet have its own production of detectors for X-ray equipment, components for them were purchased in America or China. Therefore, scientists of our Center, together with the University of Science and Technology MISIS, have developed a prototype of a new generation detector. It is an optoelectronic converter based on an innovative perovskite to translate X-rays into an electronic signal. The development is already being tested, in the future this will allow organizing its own production of such detectors. They are noticeably superior in their characteristics to the analogues now used. Their implementation will help make radiation research more accessible, "said Yuri Vasiliev, a representative of the Center for Diagnostics and Telemedicine of DZM.

According to representatives of the Center for Diagnostics and, telemedicine DZM detectors can also be used as registration of X-rays space in orbiters, special devices for monitoring the conditions of metal structures, devices for inspection medical and diagnostics.

Creating an X-ray detector is a multi-step process. The work uses laser scribing of the substrate surface to create microdimensional channels, then thin layers of transport materials and perovskite are applied to the surface using slot matrix printing and centrifugation. Then, thermoresistive sputtering of metal is performed to create contacts. The resulting instrument structure is being tested, which is a study of the photocurrent that is generated in the detector during irradiation, "said Andrei Morozov, a researcher at the Laboratory of Promising Solar power at MISIS University.

Development is still at an early stage, despite the presence of a prototype. To bring the technology to the stage of industrial application, it will take at least a year of research. In the future, scientists plan to work to increase the uniformity of the dark current of the detector pixels and the sensitivity of pixels to radiation.