GaN-based power devices: Physics, reliability, and perspectives
GaN-based power devices: Physics, reliability, and perspectives
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DOI：
10.1063/5.0061354
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发表时间：
2021-11-08
影响因子：
3.2
通讯作者：
Matioli, Elison
中科院分区：
文献类型：
--
作者：
Meneghini, Matteo;De Santi, Carlo;Matioli, Elison
在过去的十年中，氮化镓（GaN）已成为制造功率器件的优良材料。在市场上已上市的功率器件的半导体中，GaN具有最宽的能隙、最大的临界场和最高的饱和速度，因此代表了用于制造高速/高压元件的优良材料。由于AlGaN/GaN异质结构的使用，自发和压电极化的存在使我们能够在没有任何掺杂的情况下产生具有高迁移率和大沟道密度的二维电子气。这有助于最大限度地减少电阻损耗;同时，对于GaN晶体管，由于寄生电容和开关电荷小，开关损耗非常低。器件缩放和单片集成实现了高频操作，从而在小型化方面具有优势。对于高功率/高电压操作，垂直器件架构正在被提出和研究，并且三维结构-鳍形、沟槽结构、基于MEMS的结构-正显示出巨大的潜力。与Si相反，GaN是一种相对年轻的材料：必须详细了解和描述捕获和退化过程，以优化器件的稳定性和可靠性。本文介绍了GaN基功率器件的物理、技术和可靠性：在文章的第一部分，从讨论材料的主要特性开始，详细讨论了横向和垂直GaN晶体管的特性，为这一复杂而有趣的领域提供指导。论文的第二部分着重于陷阱和可靠性方面：详细讨论了GaN中陷阱的物理起源和主要的退化机制。广泛的参考论文和对最相关方面的见解为读者提供了对当前和下一代GaN电子产品的全面概述。
Over the last decade, gallium nitride (GaN) has emerged as an excellent material for the fabrication of power devices. Among the semiconductors for which power devices are already available in the market, GaN has the widest energy gap, the largest critical field, and the highest saturation velocity, thus representing an excellent material for the fabrication of high-speed/high-voltage components. The presence of spontaneous and piezoelectric polarization allows us to create a two-dimensional electron gas, with high mobility and large channel density, in the absence of any doping, thanks to the use of AlGaN/GaN heterostructures. This contributes to minimize resistive losses; at the same time, for GaN transistors, switching losses are very low, thanks to the small parasitic capacitances and switching charges. Device scaling and monolithic integration enable a high-frequency operation, with consequent advantages in terms of miniaturization. For high power/high-voltage operation, vertical device architectures are being proposed and investigated, and three-dimensional structures-fin-shaped, trench-structured, nanowire-based-are demonstrating great potential. Contrary to Si, GaN is a relatively young material: trapping and degradation processes must be understood and described in detail, with the aim of optimizing device stability and reliability. This Tutorial describes the physics, technology, and reliability of GaN-based power devices: in the first part of the article, starting from a discussion of the main properties of the material, the characteristics of lateral and vertical GaN transistors are discussed in detail to provide guidance in this complex and interesting field. The second part of the paper focuses on trapping and reliability aspects: the physical origin of traps in GaN and the main degradation mechanisms are discussed in detail. The wide set of referenced papers and the insight into the most relevant aspects gives the reader a comprehensive overview on the present and next-generation GaN electronics.