Title :
A novel cubic X-ray detector diode with isotropic response for high-energy radiation dosimetry
Author :
Norlin, P. ; Oberg, O. ; Junique, S. ; Kaplan, Wlodek ; Andersson, Jon ; Nilsson, G.
Author_Institution :
Acreo Swedish ICT AB, Stockholm, Sweden
Abstract :
A novel X-ray detector diode, optimized for angular independent (isotropic) dose response, is presented. The diode is designed as a silicon cube with pn-junctions on all six sides, which creates a close to 3D symmetrical device. The cube edge is 300 μm or 410 μm. It is manufactured by a micromachining based process featuring deep reactive ion etching of silicon-on-insulator substrates, doping of vertical walls from gas phase and refill of etched trenches with polysilicon. For 6 MV X-rays, in the ±30° beam angle range, the variation in detector response was at best ±0.5% for a cubic diode compared to ±3.3% for conventional diodes, a factor 7 improvement.
Keywords :
X-ray detection; dosimetry; elemental semiconductors; etching; micromachining; p-n junctions; semiconductor device manufacture; semiconductor diodes; semiconductor doping; silicon; silicon-on-insulator; sputter etching; 3D symmetrical device; Si; angular independent dose response; cubic X-ray detector diode; deep reactive ion etching; high-energy radiation dosimetry; isotropic dose response; micromachining based process; pn-junction; silicon-on-insulator substrate; size 300 mum; size 410 mum; vertical wall doping; voltage 6 MV; Biomedical applications of radiation; Detectors; Dosimetry; Semiconductor diodes; Silicon; X-ray detectors; X-ray detector; angular independence; cube; diode; dosimetry; isotropic response; radiation therapy; silicon;
Conference_Titel :
Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS & EUROSENSORS XXVII), 2013 Transducers & Eurosensors XXVII: The 17th International Conference on
Conference_Location :
Barcelona
DOI :
10.1109/Transducers.2013.6626700
