[en] A possibility to fabricate the Si radial position-sensitive detector with the linear response is shown. The detector is based on the graded resistive layer obtained by the lithium diffusion at the diffusion temperature gradient along the sample radius. The detector diameter is 38 mm and thickness 570 μm. The detector position resolution for α-particles of ²⁴¹Am is 0.28 mm. The temperature conditions of the lithium diffusion into silicon are calculated. A good agreement of the experimental results with the calculated values is obtained. The nonlinearity of the detector respons is >= 1%