Schottky barrier detectors based on high quality 4H-SiC semiconductor: Electrical and detection properties

• Published in: Applied surface science 2018-12, Vol.461, p.276-280
• Main Authors: Zaťko, B., Hrubčín, L., Šagátová, A., Osvald, J., Boháček, P., Zápražný, Z., Sedlačková, K., Sekáčová, M., Dubecký, F., Skuratov, V.A., Korytár, D., Nečas, V.
• Format: Article
• Language: English
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2018.07.008

•Schottky diodes based on 4H-SiC high quality epitaxial layer were fabricated.•The typical reverse current of measured diodes was below 30 pA up to bias of 500 V.•Calculated Schottky barrier height varies from 1.10 eV up to 1.27 eV.•The spectrometric performance of structures were tested using various sources of radiation.•The irradiation of detector structures was realized with Xe ions and electrons. In this work we have focused on characterization of the surface barrier detectors on high quality 4H-SiC epitaxial layer. The thickness of the layer was 70 μm and the diameter of circular Au/Ni Schottky contact was 2 mm. The forward and the reverse current-voltage characteristics of fabricated diode structures were measured. From the forward characteristics the Schottky barrier height, ideality factor and series resistance were calculated and from reverse characteristics the operational voltage of detectors was determined. The spectrometric performance of selected detector structures were tested using various sources of radiation like 238Pu, 226Ra (α-particles) and 241Am (X- and γ-rays) and showed the high energy resolution. Detector structures were irradiated with 165 MeV 132Xe23+ ions and 5 MeV electrons up to a fluency of 1.5 × 1010 cm−2 and 1.1 × 1014 cm−2, respectively. The degradation of the spectrometric performance was observed and evaluated.