GaN-Based Transistors with Trigate Architecture

GaN HEMT（High Electron Mobility Transistor，高电子迁移率晶体管）近来已成为流行的器件，特别是在功率开关和RF（Radio Frequency，射频）功率放大器中的应用。功率开关和RF放大器是现代信息和通信技术的关键部件。GaN晶体管在这些元件中的应用提供了许多优点，因此GaN晶体管，特别是GaN HEMT的发展被积极地推进。迄今为止实现的大多数GaN HEMT是在零施加栅极电压下具有导电沟道的dHEMT（耗尽HEMT）。这严重限制了它们的潜在应用领域，因为频繁地需要对于零栅极电压关断的eHEMT（增强型HEMT）。本项目的重点是一个新的和有前途的晶体管架构，即三栅极的概念，成为流行的硅电子最近。 本项目将把这一概念应用到GaN HEMT中，并对GaN三栅eHEMT进行深入研究。这三个项目合作伙伴在晶体管理论和GaN技术方面拥有公认的专业知识，他们将对GaN三栅极结构进行研究，特别关注用于功率开关和RF放大器的GaN三栅极eHEMT。他们将密切合作，-详细研究GaN三栅极eHEMT的物理和操作，-精心设计用于功率开关和RF应用的此类晶体管，-开发并建立GaN三栅极eHEMT的完整工艺流程，-制造GaN三栅极eHEMT并对这些晶体管进行彻底的电气表征，- 评估GaN三栅极概念的潜力。将进行广泛的器件模拟，以深入了解GaN三栅极HEMT的物理和操作。所得到的结果作为基础，阐述合适的设计的三栅极eHEMT的功率开关和RF应用。从加工的角度来看，主要挑战是通过蚀刻深沟槽来制造用于三栅HEMT的AlGaN/GaN主体，从而避免在主体侧壁形成缺陷，以及在侧壁上沉积金属和电介质。该项目的主要目标是（i）实现与传统GaN顶栅HEMT成功竞争的GaN三栅eHEMT，（ii）显著提高GaN三栅HEMT的知识水平，以及（iii）对这些晶体管的潜力进行有根据的关键评估。

GaN HEMTs (High Electron Mobility Transistor) have become popular devices recently, in particular for application in power switches and RF (Radio Frequency) power amplifiers. Power switches and RF amplifiers are key components for modern information and communication technology. The application of GaN transistors in these components offers many advantages and therefore the development of GaN transistors, in particular GaN HEMTs, is pushed forward aggressively. Most GaN HEMTs realized so far are dHEMTs (depletion HEMT) having a conducting channel at zero applied gate voltage. This seriously limits their potential application areas since frequently eHEMTs (enhancement HEMT) are needed that for zero gate voltage are switched off. The present project is focused on a new and promising transistor architecture, namely the trigate concept that became popular in silicon electronics quite recently. In the project, this concept will be adopted to GaN HEMTs and in-depth research on GaN trigate eHEMTs will be carried out. The three project partners with recognized expertise in transistor theory and GaN technology will conduct research on GaN trigate structures with special emphasis on GaN trigate eHEMTs for power switches and RF amplifiers. They will closely collaborate and - investigate the physics and operation of GaN trigate eHEMTs in detail,- elaborate suitable designs of such transistors for power switches and RF applications,- develop and establish a complete process flow for GaN trigate HEMTs, - fabricate GaN trigate eHEMTs and perform a thorough electrical characterization of these transistors,- assess the potential of the trigate concept for GaN.Extensive device simulations will be performed to get insights in the physics and operation of GaN trigate HEMTs. The obtained results serve as basis for elaborating suitable designs of trigate eHEMTs for power switches and RF applications. From the processing point of view, major challenges are the fabrication of the AlGaN/GaN bodies for trigate HEMTs by etching deep trenches, thereby avoiding the formation of defects at the body sidewalls, and the deposition of metals and dielectrics on the sidewalls. Key targets of the project are (i) the realization of GaN trigate eHEMTs that successfully compete with conventional GaN top-gate HEMTs, (ii) a significant enhancement of the state of knowledge on GaN trigate HEMTs, and (iii) a well-founded and critical assessment of the potential of these transistors.