雜談GaN技術

隨著人工智慧（AI）、機器人和太空系統重新定義功率電子學的可能性，氮化鎵（GaN）技術持續引領這一變革。在最近接受 Electronic Product Design & Test (EPDT) 的採訪中，EPC 的執行長兼共同創辦人 Alex Lidow 博士分享了他對 GaN 如何重塑半導體格局的見解——以及這項快速發展的技術未來的發展方向。

隨著全球對光伏（PV）系統需求的增長，製造商面臨降低成本同時保持可靠性的巨大壓力。創新技術對於實現這些目標至關重要，尤其是在商業和住宅光伏系統中。這些系統通常分為兩種主要配置：微型逆變器和串式逆變器。

氮化鎵(GaN)是一種全新的使能技術，可實現更高的效率、顯著減小系統尺寸、更輕和在應用中取得矽元件無法實現的性能。那麽，為什麽關於氮化鎵半導體仍然有如此多的誤解？事實又是怎樣的呢？

移動性是所有經濟體的重要驅動因素。電子移動性（或 e-Mobility）是一種清潔且具影響力的方式，可以在不增加環境壓力的情況下保持商業運轉，避免低效能引擎或燃燒化石燃料引擎對我們星球造成的損害。對於高效且緊湊的電機驅動設計需求日益增加。EPC 的基於 GaN 的電機驅動參考設計正在開發中，以啟動支持這一趨勢的競爭性和環保替代方案。

48 V 正在被許多應用採用，包括 AI 系統、數據中心和輕度混合動力電動車。然而，傳統的 12 V 生態系統仍然占主導地位，因此需要高功率密度的 12 V 至 48 V 升壓轉換器。eGaN® FET 的快速開關速度和低 RDS(on) 可以幫助解決這一挑戰。在本文中，評估了使用 eGaN FET 直接驅動 eGaN FET 兼容的 Renesas ISL81807 控制器 IC 的簡單低成本同步升壓拓撲設計的 12 V 至 48 V、500 W 直流-直流電源模塊。

簡介：感謝科羅拉多大學博爾德分校 | CUB · 電機、計算機與能源工程系 (ECEE) 的作者和貢獻。  

Written by Michael de Rooij and Alana Nakata - Efficient Power Conversion

Published in: PCIM Europe 2017; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management; Proceedings of

eGaN FETs, which are available in non-traditional chip scale packages (CSP) as land grid array (LGA) and/or ball grid array (BGA) formats, have repeatedly demonstrated higher power density and higher efficiency performance than equivalent MOSFETs across various applications ^{[1, 2]}. Those improvements are contingent upon proper layout practices documented extensively in ^{[1, 3]} that minimize unwanted parasitic elements. Over the seven years since eGaN FETs were first launched into the market there have been a total of 127 device failures out of a total of more than 17 billion hours in actual use in the field, 75 of which were a result of poor assembly technique or poor printed circuit board (PCB) design practices ^[4]. Designers are becoming more familiar with the PCB design rules that affect manufacturability and are less forgiving compared to MOSFETs due to their relatively smaller sizes. This paper will cover the various guidelines for PCB design that maximize the performance of eGaN FETs and reliability yet still rely on existing PCB manufacturing capabilities.

Gallium nitride (GaN) is a better semiconductor than silicon. There are many crystals that are better than silicon, but the problem has always been that they are far too expensive to be used in every application where silicon is used. But, GaN can be grown as an inexpensive thin layer on top of a standard silicon wafer enabling devices that are faster, smaller, more efficient, and less costly than their aging silicon counterparts.

Televisions can get their content wirelessly, but there is one set of wires they still need: those in their power cord. The consumer electronics industry has floated ideas for freeing TVs from their power cords, but this goal remains elusive. There are several reasons, such as the difficultly of meeting high-power requirements for large-screen TVs and the need for identifying an economical technology. Nevertheless, eGaN FETs could play a role in making TVs truly cordless devices.

The previous installment in this series focused on the physics of failure surrounding thermo-mechanical reliability of EPC eGaN® wafer level chip-scale packages. A fundamental understanding of the potential failure modes under voltage bias is also important. This installment will provide an overview of the physics of failure associated with voltage bias at the gate electrode of gallium nitride (GaN) field effect transistors (FETs). Here we look at the case of taking the gate control voltage to the specified limit and beyond to investigate how eGaN FETs behave over a projected lifetime.