100 Mev Ag and 25 Kev He Induced Defects in 4H-SiC

• Published in: ECS transactions 2022-04, Vol.107 (1), p.439-444
• Main Authors: Chakravorty, Anusmita, Kabiraj, Debdulal
• Format: Article
• Language: English
• ISSN: 1938-5862; 1938-6737
• DOI: 10.1149/10701.0439ecst

We demonstrate the formation of radiative defects, known as color centres, in 100 MeV Ag and 25 keV He irradiated semi-insulating 4H-SiC using low-temperature (~77 K) photoluminescence (PL). In PL, the luminescence resulting from radiative recombination of photo-excited carriers (electrons and holes) is studied. In our work, a 266 nm deep UV excitation source is utilized for performing PL measurements. In the range, 850-1150 nm, the photoluminescent peaks ascribed to silicon vacancies ( V Si ) and unknown defect-related bands (UD 3 and UD 4 ) are observed after both ion irradiations. It has also been observed that till an optimum irradiation fluence there is an enhancement of photoluminescence from the ion irradiation-induced defects but further increase in irradiation fluence results in accumulation of photo-absorbing defects, providing pathways for non-radiative processes. In addition, ion irradiation has been shown to suppress the undesirable luminescence in the range 300-600 nm caused by the intrinsic defects in as-grown 4H-SiC.