Radiation detectors made of CVD diamond films

Polycrystalline diamond films ↑

Growth surface of CVD diamond film.

A diamond film of detection quality up to 350 μm thick was synthesized by chemical deposition from the gas phase (with activation of a carbon-hydrogen mixture by glow discharge stabilized by magnetic field). [E.P.Bereznyak et al.]

We investigated the material physical properties in dependence on thermal treatment, chemical etching, irradiation and ways of contact application.

The developed growth process allows to achieve the sample resistivity of ~ 10¹⁴ Ohm×cm.

Radiation detectors made of CVD diamond films ↑

I-V characteristics of CVD diamond after different stages of treatment.

Interdigitated Al contacts on the growth surface of the diamond film (×50).

Pulse-height distributions of the detector signal from ²³⁹Pu α-source for different displacement voltages.

Displacement-voltage dependence of the pulse count-rate of the diamond detector exposed to α-particles.

Registration of intensive gamma and electron radiation with CVD diamond detectors at linac LU-10. ↑

Scheme of electron-beam registration at the accelerator LU-10.

The diamond detector signal at a displacement voltage of 80 V.

Signals from the diamond detector (channel 1) and Faraday cup (channel 2); U_d = 80 V.

Dependence of the detector signal amplitude on the displacement voltage.

Dosimetry of electron radiation with CVD diamond detectors ↑

We manufactured radiation-proof diamond detectors, packaged within a completely metal construction. They are intended for detecting high-intensity electron and gamma radiation and can be used for in-core reactor dosimetry.

The detectors analog sensitivity was measured at LU-10 accelerator under combined irradiation from Bremsstrahlung and 10 MeV electrons: δ_γ=1^-10 C/Gy, δ_e=1,2^-10 C/Gy

300 μm thick diamond detector on Si substrate sized 8×8×2 mm³

Bremsstrahlung crosscut profile at LU-10 linac, measured by diamond detector.

Coordinate-sensitive diamond detector ↑

A multichannel strip diamond detector of electron- and gamma-radiation was developed for a precision measurement of the electron beam profile at the escape of accelerator. The intrastrip resistance and uniformity of electrophysical and radiation performances of the detector were investigated. [I.N.Shlyakhov et al.]

Bulk and surface leakage currents and peak height spectra are measured for different ways of connection to a recording equipment (single strip, a group of strips).

Bulk and surface leakage currents.

Count rate at an individual strip.

Pulse-height spectrum of the coordinate-sensitive detector taken from the contacts on the opposite sides of the film and on one and the same side.

Leakage currents between neighbour strips at U = 200 V.