Gallium nitride vertical power devices on foreign substrates: a review and outlook

Abstract

Vertical gallium nitride (GaN) power devices have attracted increased attention due to their superior high-voltage and high-current capacity as well as easier thermal management than lateral GaN high electron mobility transistors. Vertical GaN devices are promising candidates for next-generation power electronics in electric vehicles, data centers, smart grids and renewable energy process. The use of low-cost foreign substrates such as silicon (Si) substrates, instead of the expensive free-standing GaN substrates, could greatly trim material cost and enable large-diameter wafer processing while maintaining high device performance. This review illustrates recent progress in material epitaxy, device design, device physics and processing technologies for the development of vertical GaN power devices on low-cost foreign substrates. Although the device technologies are still at the early stage of development, state-of-the-art vertical GaN-on-Si power diodes have already shown superior Baliga's figure of merit than commercial SiC and Si power devices at the voltage classes beyond 600 V. Furthermore, we unveil the design space of vertical GaN power devices on native and different foreign substrates, from the analysis of the impact of dislocation and defects on device performance. We conclude by identifying the application space, current challenges and exciting research opportunities in this very dynamic research field.

Annealing Behavior of Vacancy‐Type Defects in Mg‐ and H‐Implanted GaN Studied Using Monoenergetic Positron Beams

“…In SiC‐based power devices, for example, the avalanche breakdown of Schottky barrier diodes or transistors can be suppressed by edge termination technologies that use the selective area doping of p‐type impurities by ion implantation. For GaN power devices, however, because of the very low activation rate of implanted acceptors, the avalanche breakdown voltage is much lower than that expected from the intrinsic properties of GaN …”

XXIII Международный симпозиум Нанофизика и наноэлектроника", Нижний Новгород, 11-14 марта 2019 г. Вертикальный полевой транзистор с управляющим p-n-переходом на основе GaAs

“…Существенной конструктивной особенностью транзистора является расположение канала протекания тока. Силовой транзистор с вертикальным каналом потенциально имеет ряд преимуществ по сравнению с горизонтальной структурой [3]: достижение высоких уровней тока и напряжения пробоя без увеличения размера схемы; более высокая надежность, связанная с большей термической стойкостью и с удалением области максимального электрического поля от поверхности в объем устройства. Важной характеристикой силовых преобразователей электрических сигналов является их быстродействие.…”

“…Тем не менее существует целый ряд физических и технологических проблем, которые необходимо решить в процессе создания приборов на основе этих полупроводников. Исследования в этом направлении интенсивно проводятся [1][2][3][4][5]. Перспективность GaAs связана, в частности, с его прямозонной структурой, малым временем жизни неосновных носителей заряда и высокой подвижностью электронов.…”

MOVPE growth of GaN on patterned 6-inch Si wafer

“…The GaN layer grown by metalorganic vapour-phase epitaxy (MOVPE) results in tensile stresses on Si wafer and in compressive stresses on sapphire [3]. For nearly two decades, AlN transition layer or thick Al x Ga 1−x N grading between Si and GaN was only method in order to suppress the formation of cracks in grown films [4]. By inserting different Al x Ga 1−x N interlayers, compressive stress is introduced to compensate the tensile stress produced during the cooling process to eliminate surface cracking.…”