Radiation detector of the DELTA E-E type with insulation trenches and its method of fabrication

摘要

A radiation detector ( 105 ) of the ”E-E type is proposed. The detector is integrated in a chip ( 205 ) of semiconductor material with a front surface ( 216 ) and a back surface ( 215 ) opposite the front surface, the detector having at least one detection cell ( 236 ) arranged on the front surface for receiving a radiation to be evaluated, wherein the detector includes: a first region ( 224,240,263 ) of a first type of conductivity extending into the chip from the front surface to a first depth; a second region ( 220,235 ) of a second type of conductivity extending into the chip from the back surface to a second depth so as to reach the first region; and for each detection cell a third region ( 255 ) of the second type of conductivity extending into the first region from the front surface to a third depth lower than the first depth and the second depth, a thin sensitive volume for absorbing energy from the radiation being defined by a junction between the first region and each third region, and a thick sensitive volume for absorbing further energy from the radiation being defined by a farther junction between the first region and the second region. For each detection cell the detector further includes insulation means ( 270 ) arranged around the third region and extending from the front surface into the first region to an insulation depth comprised between the first depth and the third depth.