Laser slice thinning of GaN-on-GaN high electron mobility transistors

As a newly developed technique to slice GaN substrates, which are currently very expensive, with less loss, we previously reported a laser slicing technique in this journal. In the previous report, from the perspective of GaN substrate processing, we could only show that the GaN substrate could be sliced by a laser and that the sliced GaN substrate could be reused. In this study, we newly investigated the applicability of this method as a device fabrication process. We demonstrated the thinning of GaN-on-GaN high-electron-mobility transistors (HEMTs) using a laser slicing technique. Even when the HEMTs were thinned by laser slicing to a thickness of 50 mm after completing the fabrication process, no significant fracture was observed in these devices, and no adverse effects of laser-induced damage were observed on electrical characteristics. This means that the laser slicing process can be applied even after device fabrication. It can also be used as a completely new semiconductor process for fabricating thin devices with thicknesses on the order of 10 mm, while significantly reducing the consumption of GaN substrates.

Automated summary

This study demonstrates a laser slicing technique for cutting GaN substrates and investigates its applicability in device fabrication. Thinning of GaN-on-GaN high-electron-mobility transistors (HEMTs) was successfully achieved using this technique, with no significant adverse effects observed on the structural and electrical properties of the devices. The laser slicing process can be applied after device fabrication, offering a new approach to fabricating thin devices with reduced consumption of GaN substrates.