During the fabrication of a MOS-HEMT, the plasma-etching steps are critical because they can damage the GaN materials and lead to electrical degradation effects. In this paper, we propose to evaluate GaN etching performances through comparing the Cl₂-based atomic layer etching (ALE) process with He or Ar as the sputtering gas. The self-limiting synergy and process window of ALE has been investigated. Based on these results, we propose the reasons for the nonself-limiting behavior of the He ALE process. Both ALE processes were compared to a steady-state process by investigating roughness, and electrical measurements, in order to evaluate the induced damage.

中文翻译：

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使用Cl2和He或Ar等离子体对GaN进行原子层蚀刻

在制造MOS-HEMT的过程中，等离子体刻蚀步骤至关重要，因为它们会损坏GaN材料并导致电性能下降。在本文中，我们建议通过比较基于He或Ar作为溅射气体的Cl ₂基原子层蚀刻（ALE）工艺来评估GaN蚀刻性能。研究了ALE的自限协同作用和过程窗口。基于这些结果，我们提出了He ALE过程非自限行为的原因。通过研究粗糙度和电学测量，将两种ALE过程与稳态过程进行比较，以评估引起的损伤。