FRONTIER DETECTORS FOR FRONTIER PHYSICS <br> 13th Pisa Meeting on Advanced Detectors <br>

First results of a novel silicon drift detector array designed for low energy X-ray fluorescence spectroscopy

May 28, 2015, 9:17 AM

Poster S6 - Solid State Detectors Solid State Detectors - Poster Session

Speaker

Mr Alexandre Rachevski (INFN Trieste)

Description

We developed a trapezoidal shaped matrix with 8 cells of Silicon Drift Detectors (SDD) featuring a very low leakage current (below 180 pA/cm^2 at 20 C) and a shallow uniformly implanted p+ entrance window that enables sensitivity of at least up to photons of oxygen K-alpha-1 emission line (524.9 eV). The matrix consists of a completely depleted volume of silicon wafer subdivided into 4 square cells, 39 mm^2 each, and 4 half-size triangular cells. The energy resolution of a single square cell, readout by the ultra-low noise SIRIO charge sensitive preamplifier, is 140 eV FWHM at 5.9 keV and 0 C. The total sensitive area of the matrix is 233 mm^2 and the wafer thickness is 450 µm. The detector was developed in the frame of the INFN R&D project ReDSoX in collaboration with FBK, Trento. Its trapezoidal shape was chosen in order to optimize the detection geometry for the experimental requirements of low energy X-ray fluorescence (LEXRF) spectroscopy, aiming at achieving a large detection angle. We plan to exploit the complete detector at the TwinMic spectro-microscopy beamline at the Elettra synchrotron (Trieste, Italy). The complete system, composed of 4 matrices, covers up to 40% of the isotopic photoemission hemisphere. This geometry provides a 10 times improvement over the present detector configuration. We report on the layout of the SDD matrix and of the experimental set-up, as well as the spectroscopic performance measured at different temperatures and bias conditions.

Presentation materials

Slides

Poster_Review_Rachevski.pptx