Performance of Silicon Microdosimetry Detectors in Boron Neutron Capture Therapy

Abstract

Reverse-biased silicon p-n junction arrays using Silicon-On-Insulator technology have been proposed as microdosimeters. The performance of such detectors in boron neutron capture therapy (BNCT) is discussed. This work provides the first reported measurements using boron-coated silicon diode arrays as microdosimeters in BNCT. Results are in good agreement with measurements with gas proportional counters. Various boron-coating options are investigated along with device orientation effects. Finally, a 235U coating is tested to simulate the behavior of the device in a heavy-ion therapy beam.

Out‐of‐field dose equivalents delivered by proton therapy of prostate cancer

“…17,18 This device has also been used extensively in hadron and proton therapy, particularly in primary beam microdosimetry measurements. 16,17,[19][20][21] In this experimental setup, the SOI microdosimeter, preamplifier, and accompanying electronics were situated within an aluminum probe assembly to allow for a low noise environment to be achieved. The wall thickness of the probe was 900 m, with a 4 m aluminum window immediately in front of the microdosimeter to allow for the transport of low range secondaries into the microdosimeter.…”

“…Such converters have been employed in previous neutron and mixed field measurements with this device. 17,20 All measurements were completed using a patient specific aperture-bolus combination, and proton energy of 225 MeV to simulate a typical radiation field delivered in a clinical prostate case. The maximum aperture diameter was 8 cm both in lateral and vertical direction.…”

A computational technique for simulating ionization energy deposition by energetic ions in complex targets

“…As previously reported [2], [3], [5], the SOI microdosimeter consists of an array of reversed biased, p-n junctions as illustrated in Figs. 1 and 2.…”

“…Silicon microdosimetry studies using SOI devices in radiation oncology have been reported previously [2]- [5]. In these studies, silicon microdosimeters were used to measure lineal energy spectra in such radiation oncology modalities as boron-neutron capture therapy (BNCT) [3], [4] and Proton therapy [2]. Recently the technique has been applied to measurements in fast neutron therapy (FNT).…”

3D Radiation Detectors: Charge Collection Characterisation and Applicability of Technology for Microdosimetry

“…The Centre for Medical Radiation Physics (CMRP) has developed three generations of microdosimeters based on silicon-on-insulator (SOI) substrates [4][5][6][7][8]. These SOI microdosimeters were based on planar and pseudo 3D mesa rectangular parallelepiped (RPP) and cylindrical SVs produced on p-SOI and n-SOI using diffusion or implantation techniques for forming laterally depleted p-i-n diodes.…”