Direct Wafer Bonding of GaN for Power Devices Applications

Abstract

Over the past decade the interest in gallium nitride – based electronic applications increased significantly. The economical advantages of GaN-based applications imposed the development of new manufacturing technologies. Among them, wafer bonding process solutions could be further developed and optimized for the manufacturing of GaN engineered substrates. The most significant benefit of using wafer bonding for GaN-based applications is the possibility to combine GaN with various substrate materials, offering a high flexibility by imposing strict quality requirements only to the surfaces of the substrates and not to their crystal structure.This work proposes two different process flows for “GaN-on-Something” substrates manufacturing. The features and benefits of the two process flows are illustrated by experimental results.

Гетерогенная Интеграция Как Один Из Путей Выхода Российской Микроэлектроники Из Кризиса

“…Еще одним интересным примером использования этой технологии является метод соединения многослойных широкозонных полупроводниковых структур на основе GaN с подложками кремния, карбида кремния или нитрида алюминия [12]. Это, в первую очередь, актуально для создания силовых и СВЧ-компонентов.…”

(Invited, Digital Presentation) Low-Temperature Direct Bonding of Wide-Bandgap Semiconductor Substrates

“…In addition, as these bonding agents have lower thermal conductivity than SiC and diamond, the bonding layer would inhibit heat dissipation from devices to heat spreaders. Thus, many researchers have developed direct bonding techniques of semiconductor materials with thermally conductive materials 5,6 . A common bonding method is fusion bonding; however, process temperatures over 1000 °C are Low-Temperature Direct Bonding of Wide-Bandgap Semiconductor Substrates required to bond the SiC and diamond substrates 7,8 , resulting in cracks in the bonded substrate.…”

Hydrophilic direct bonding of GaN and Si substrates by wet treatments using H2SO4/H2O2 mixture and NH3/H2O2 mixture

“…Direct bonding of GaN and Si substrates was achieved by surface activated bonding (SAB). 20,21) In SAB, the GaN and Si surfaces were sputter-etched and contacted with each other. The bonding interface was composed of the amorphous Si and GaN intermediate layer with a thickness of ∼2-5 nm.…”