Large-Area 4H-SiC Ultraviolet Avalanche Photodiodes Based on Variable-Temperature Reflow Technique

High‐uniformity 1 × 64 linear arrays of silicon carbide avalanche photodiode

“…For fabrication of 1 × 64 4H‐SiC APD linear arrays, the pixels were isolated with each other by positively bevelled mesa (angle = 8°). In order to reduce the process variation, an variable‐temperature reflow technique in [9] and multi‐cycle ICP dry etching was adopted for the bevelled mesa formation, during which the wafers were rotated with a small angle for each cycle etching process. The RF power and etching time of multi‐cycle ICP are optimised with an etching cycle of 2 min for the mesa creation.…”

“…Introduction: Silicon carbide (SiC) avalanche photodiodes (APDs) have been greatly investigated in recent years as the candidates for ultraviolet (UV) detectors to replace the conventional expensive, bulky and fragile photomultiplier tubes, which is of very importance in many applications such as flame detection, astronomical research, biochemical analysis and UV communication [1][2][3][4][5][6][7][8][9][10]. However, most of the previously reported works focus on the discrete device, while the research on 4H-SiC APD arrays is barely reported [11][12][13][14].…”

Optimization Strategy of 4H-SiC Separated Absorption Charge and Multiplication Avalanche Photodiode Structure for High Ultraviolet Detection Efficiency

“…In order to eliminate premature breakdown and suppress leakage current that are caused by the junction termination, positive beveled mesas with a small inclination angle are usually adopted when fabricating 4H-SiC APDs [13][14][15][16]18]. However, the angles of the positive beveled mesa adopted in previous reports are various.…”

“…In the past few decades, Cree Company has greatly promoted epitaxial growth technology for SiC films, which thus has further led to the continuous improvement for crystalline quality. Most recently, Zhou et al have proposed a variable-temperature photoresist reflow technique to create very smooth sidewalls for the beveled 4H-SiC APD mesa [18], which enables a high multiplication gain of over 10 6 and a low dark current of~0.2 nA/ cm 2 . Nevertheless, the previous research has more focused on improving the material quality and optimizing the fabrication technology for SACM APDs [19][20][21], while the impact of structural design on photogenerated carrier transport and photocurrent detectivity has been rarely discussed till now.…”

Preparation and photoelectric properties of SnOx films with tunable optical bandgap

“…Ultraviolet (UV) photodetector can find many applications, such as fire detection, ozone monitoring, chemical analysis and defense technology etc. Due to the relatively large photon energy of UV light, wide bandgap semiconductor materials, such as ZnO [1][2][3] , Ga2O3 [4][5][6] , SiC [7][8] , GaN [9][10] and MgO 11 etc, are commonly used in the production of UV photodetectors. The extensive research into wide bandgap semiconductors has led to the emergence of new material systems, such as stannous oxide (SnO) and tin oxide (SnO2), suitable for UV photodetection.…”