In nuclear-physics experiments, primarily telescopic systems consisting of dE/dx-SCD with 20-200 µm thick sensitive region are used to identify particles [1,2]. Such a structure of telescopic systems permits identifying and investigating, specifically, the spectral composition of charged particles with different energy, charge, and mass.The present work is devoted to studying a universal telescopic detector based on a p-i-n type Si(Li) nuclear-radiation detector with an extended 10-20 mm thick sensitive region in one silicon single-crystal.The telescopic detector is built on the basis of a p-i-n type Si(Li) structure. A dE/dx detector is present on one side and the remaining part consists of total-absorption detectors. A special feature of such a detector is that an ionizing particle strikes the lateral surface. In [3], it is shown that Si(Li) detectors operate efficiently with parallel and perpendicular incidence of the ionizing particles relative to the electric field. They can be used to detect long-range charged particles. Figure 1 shows the overall view of a telescopic detector. A thin dE/dx layer is formed on the lateral surface of the detector by means of a narrow channel on the diffusion n + -region side, reaching the depth of the high-resistance i region. A thin protective layer is created on this side of the surface; this layer provides a so-called entrance window -a "dead" layer. Such channels are cut in parallel on the subsequent E detectors. The distance between the channels is set by discrete Si(Li) detectors whose sensitive region has a different thickness according to their function in telescopic systems [2]. The particles in such a telescopic detector are detected in one crystal on the lateral surface side, where a thin dead layer is formed.A dislocation-free p-type silicon single crystal was used as the initial material to fabricate a telescopic detector. A diamond disk was used to cut 30 × 20 × 7 mm plates parallel to the 〈111〉 plane from this crystal (see Fig. 1). The lithium (n + layer) was deposited on the ground surface of the crystal to depth 300-400 µm at 450°C in 3 min. Chemical etching was performed in a polishing composition HF:HNO 3 :CH 3 COOH (1:3:1). Next, lithium ions were allowed to drift in an electric field U = 300-600 V at 100°C for 1100-1200 h to obtain a compensated i region. The i region was 6 mm (see Fig. 1, position 7). After drift was completed, a wire saw was used to cut extended 100-300 µm deep channels on the diffusion region (n + ) side (position 6). The result was that extended 0.4-0.6 mm deep and 200 µm wide channels separated by 0.4-4 mm were obtained (1, 2, 3, ..., m). Next, certain chemical-technological operations were performed. The electric contacts were obtained by depositing aluminum on each strip through a mask. Aluminum was sputtered over the entire surface on the opposite side (position 8). After this, the structure was placed inside a case. The measurements were performed with an ionizing particle incident perpendicular to the applied electric field on t...

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