Application of Additional Leveling Drift Process to Improve the Electrophysical Parameters of Large Sized Si (Li) p-i-n Structures

The development of large sized Si (Li) detectors (with a sensitive region diameter more than 110 mm), with high energy and positional resolutions, signal linearity over a wide energy range, for alpha, beta and gamma particles is still a rather difficult technological task. This work proposes a technology to improve manufacturing procedure of p-i-n structured Si(Li) detectors. We consider a method of additional “leveling” drift to already prepared Si (Li) detectors to reach a uniformly compensated sensitive region throughout the entire volume, and to smooth out local areas of uncompensated detector regions at a certain temperature and electric field. Experimentally obtained results show that conducting an additional “leveling” drift process ensures uniform distribution of lithium ions in silicon and is one of the main technological operations. The choice of the temperature-time regime of the “leveling” drift depends on the specific resistance of the initial material. Therefore, an additional “leveling” drift was carried out on detectors obtained by p-type monocrystalline silicon with high resistance (obtained by the float-zone method) and with low resistance (obtained by the Czochralski method), and their electrophysical responses were compared. Consequently, it was determined that for low-resistance materials, “leveling” drift is more effective.