Hadron-therapy beam monitoring: Towards a new generation of ultra-thin p-type silicon strip detectors

Conference · Fri Jul 01 00:00:00 EDT 2011

DOI:https://doi.org/10.1109/ANIMMA.2011.6172968· OSTI ID:22039791

Bouterfa, M; Aouadi, K ^[1]; Bertrand, D ^[2]; Olbrechts, B; Delamare, R ^[1]; Raskin, J P; Gil, E C ^[3]; Flandre, D ^[1]

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1. Inst. of Information and Communication Technologies, Electronics and Applied Mathematics ICTEAM, Universite Catholique de Louvain, 1348 Louvain-la-Neuve (Belgium)
2. Particle Therapy Dept., Ion Beam Application IBA, 1348 Louvain-la-Neuve (Belgium)
3. Institut de Recherche en Mathematique et Physique IRMP, Universite Catholique de Louvain, 1348 Louvain-la-Neuve (Belgium)

Hadron-therapy has gained increasing interest for cancer treatment especially within the last decade. System commissioning and quality assurance procedures impose to monitor the particle beam using 2D dose measurements. Nowadays, several monitoring systems exist for hadron-therapy but all show a relatively high influence on the beam properties: indeed, most devices consist of several layers of materials that degrade the beam through scattering and energy losses. For precise treatment purposes, ultra-thin silicon strip detectors are investigated in order to reduce this beam scattering. We assess the beam size increase provoked by the Multiple Coulomb Scattering when passing through Si, to derive a target thickness. Monte-Carlo based simulations show a characteristic scattering opening angle lower than 1 mrad for thicknesses below 20 {mu}m. We then evaluated the fabrication process feasibility. We successfully thinned down silicon wafers to thicknesses lower than 10 {mu}m over areas of several cm{sup 2}. Strip detectors are presently being processed and they will tentatively be thinned down to 20 {mu}m. Moreover, two-dimensional TCAD simulations were carried out to investigate the beam detector performances on p-type Si substrates. Additionally, thick and thin substrates have been compared thanks to electrical simulations. Reducing the pitch between the strips increases breakdown voltage, whereas leakage current is quite insensitive to strips geometrical configuration. The samples are to be characterized as soon as possible in one of the IBA hadron-therapy facilities. For hadron-therapy, this would represent a considerable step forward in terms of treatment precision. (authors)

• OSTI ID: 22039791
• Resource Relation: Conference: ANIMMA 2011: 2. International Conference on Advancements in Nuclear Instrumentation, Measurement Methods and their Applications, Ghent (Belgium), 6-9 Jun 2011; Other Information: Country of input: France; 14 refs.; IEEE Catalog Number: CFP1124I-CDR
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
62 RADIOLOGY AND NUCLEAR MEDICINE
43 PARTICLE ACCELERATORS
ACCURACY
BEAM MONITORING
BREAKDOWN
COULOMB SCATTERING
DOSIMETRY
ENERGY LOSSES
HADRONS
LEAKAGE CURRENT
MONTE CARLO METHOD
PARTICLE BEAMS
QUALITY ASSURANCE
SI SEMICONDUCTOR DETECTORS
SILICON
SUBSTRATES
THERAPY
THICKNESS
TWO-DIMENSIONAL CALCULATIONS