Defect characterization of β-Ga₂O₃ single crystals grown by vertical Bridgman method

Abstract

The characteristics of structural defects observed on (100) wafers in β-Ga2O3 single crystals grown by directional solidification in a vertical Bridgman furnace were studied in terms of crystal growth conditions. No high-dislocation-density regions near the wafer periphery were observed owing to the lack of adhesion between the as-grown crystal ingot surface and the crucible inner wall, and directional solidification growth in a crucible with a very low temperature gradient resulted in β-Ga2O3 single crystals with a low mean dislocation density of 2.3 × 103 cm−2. Line-shaped defects up to 150 µm long in the [010] direction were detected at a mean density of 0.5 × 102 cm−2, which decreased with decreasing growth rate. The line-shaped defect structure and formation mechanism were discussed.

Nanocrystalline Ga2O3 films deposited by spray pyrolysis from water-based solutions on glass and TCO substrates

“…An extensive review of Ga 2 O 3 material properties, processing routes and devices was recently published by Pearton et al, 3 while b-Ga 2 O 3 , in particular, was reviewed by Park et al 4 The material has, indeed, found a wide range of applications in various disciplines. Single-crystals of Ga 2 O 3 were synthesized by low-cost, melt growth techniques 5 and were implemented in power electronic devices with high breakdown voltages, as replacements for the costly SiC and GaN. 6 Thin layers of Ga 2 O 3 have been applied in solar cells, for example as an ultrathin tunneling layer in dye-sensitized solar cells 7 or as a passivation layer on silicon solar cells.…”

Revelation of Dislocations in β‐Ga2O3 Substrates Grown by Edge‐Defined Film‐Fed Growth

“…Etching temperature was optimized over the range of 200–490 °C for the purpose of dislocation revelation. In comparison with KOH aqueous solution, molten alkali solution allows chemical etching above 100 °C. Activation energy of chemical reaction was calculated using temperature‐dependent etch rate.…”

“…A Baliga low‐frequency figure of merit over 3000 times greater than Si, and several times greater than competitive WBG power semiconductors such as 4H‐SiC and wurtzite GaN, has been predicted . Because of the availability of high‐purity Ga 2 O 3 melt, β‐Ga 2 O 3 can be grown by a variety of melt growth methods, including edge‐defined film‐fed growth (EFG), floating zone (FZ), Czochralski (CZ), and vertical Bridgman (VB) . This gives β‐Ga 2 O 3 a great advantage over 4H‐SiC and GaN in terms of wafer cost and wafer diameter.…”

Солнечно-слепые детекторы УФ-излучения на основе пленок beta-Ga-=SUB=-2-=/SUB=-O-=SUB=-3-=/SUB=-

“…с шириной запрещенной E g ≥ 4 эВ. Среди большого разнообразия широкозонных материалов оксид галлия оказывается одним из наиболее перспективных полупроводников для разработки детек-торов УФ-излучения [9,10]. Среди пяти полиморфных фаз оксида галлия фаза β-Ga 2 O 3 является наиболее стабильной вплоть до температуры плавления 1800 • C [11].…”