Dataset Information

Technical Note: Characterization of the new microSilicon diode detector.

ABSTRACT:

Purpose

Dosimetric properties of the new microSilicon diode detector (60023) have been studied with focus on application in small-field dosimetry. The influences of the dimensions of the sensitive volume and the density of the epoxy layer surrounding the silicon chip of microSilicon have been quantified and compared to its predecessor (Diode E 60017) and the microDiamond (60019, all PTW-Freiburg, Germany).

Methods

Dose linearity has been studied in the range from 0.01 to 8.55 Gy and dose-per-pulse dependence from 0.13 to 0.86 mGy/pulse. The effective point of measurement (EPOM) was determined by comparing measured percentage depth dose curves with a reference curve (Roos chamber). Output ratios were measured for nominal field sizes from 0.5 × 0.5 cm² to 4 × 4 cm² . The corresponding small-field output correction factors, k, were derived with a plastic scintillation detector as reference. The lateral dose-response function, K(x), was determined using a slit beam geometry.

Results

MicroSilicon shows linear dose response (R² = 1.000) in both low and high dose range up to 8.55 Gy with deviations of only up to 1% within the dose-per-pulse values investigated. The EPOM was found to lie (0.7 ± 0.2) mm below the front detector's surface. The derived k for microSilicon (0.960 at s_eff = 0.55 cm) is similar to that of microDiamond (0.956), while Diode E requires larger corrections (0.929). This improved behavior of microSilicon in small-fields is reflected in the slightly wider K(x) compared to Diode E. Furthermore, the amplitude of the negative values in K(x) at the borders of the sensitive volume has been reduced.

Conclusions

Compared to its predecessor, microSilicon shows improved dosimetric behavior with higher sensitivity and smaller dose-per-pulse dependence. Profile measurements demonstrated that microSilicon causes less perturbation in off-axis measurements. It is especially suitable for the applications in small-field output factors and profile measurements.

SUBMITTER: Schonfeld AB

PROVIDER: S-EPMC6852691 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Publications

Technical Note: Characterization of the new microSilicon diode detector.

Schönfeld Ann-Britt AB Poppinga Daniela D Kranzer Rafael R De Wilde Rudy Leon RL Willborn Kay K Poppe Björn B Looe Hui Khee HK

Medical physics 20190731 9

<h4>Purpose</h4>Dosimetric properties of the new microSilicon diode detector (60023) have been studied with focus on application in small-field dosimetry. The influences of the dimensions of the sensitive volume and the density of the epoxy layer surrounding the silicon chip of microSilicon have been quantified and compared to its predecessor (Diode E 60017) and the microDiamond (60019, all PTW-Freiburg, Germany).<h4>Methods</h4>Dose linearity has been studied in the range from 0.01 to 8.55 Gy a ...[more]

PMID: 31309594

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Dataset Information

Technical Note: Characterization of the new microSilicon diode detector.

Purpose

Methods

Results

Conclusions

Publications

Technical Note: Characterization of the new microSilicon diode detector.

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