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Low interface trap density in AlGaN/GaN Metal-Insulator-Semiconductor High-Electron-Mobility Transistors on CVD-Diamond

MetadataDetails
Publication Date2020-04-01
AuthorsKumud Ranjan, S. Arulkumaran, Geok Ing Ng, Abhinay Sandupatla
InstitutionsNanyang Technological University
Citations3

The interface trap behavior in SiNx/AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (MIS-HEMTs) and Schottky HEMTs on CVD diamond was studied using parallel conductance techniques. In MISHEMTs, two different types of traps were identified, fast with the time constant <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”&gt;&#36;\tau_&#123;\mathbf&#123;T&#125;&#125;\equiv(\mathbf&#123;0.1&#125;-\mathbf&#123;3.6&#125;)\mu\mathbf&#123;s&#125;&#36;&lt;/tex> and slow with <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”&gt;&#36;\tau_&#123;\mathbf&#123;T&#125;&#125;\equiv\mathbf&#123;6&#125;&#36;&lt;/tex> ms whereas, only fast traps were obtained in conventional HEMTs. These fast traps could be related to AlGaN/GaN hetero-interface which are identical in both the devices. The density of fast trap <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”&gt;&#36;(\pmb&#123;D&#125;_&#123;\mathbf&#123;TT&#125;&#125;)&#36;&lt;/tex> is almost similar for MIS-HEMTs and HEMTs (∼of <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”&gt;&#36;\mathbf&#123;0.7&#125;-\mathbf&#123;8\ x\ 10}^{\mathbf{11}}\mathbf{cm}^{-\mathbf{2}}\mathbf{eV}^{-\mathbf{1}})$</tex> . The density of slow trap <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”&gt;&#36;(\pmb&#123;D&#125;_&#123;\mathbf&#123;Ts&#125;&#125;)&#36;&lt;/tex> in MIS-HEMTs was estimated as <tex xmlns:mml=“http://www.w3.org/1998/Math/MathML” xmlns:xlink=“http://www.w3.org/1999/xlink”&gt;&#36;\sim\mathbf&#123;6&#125;-\mathbf&#123;11\ x\ 10}^{\mathbf{12}}\mathbf{cm}^{-\mathbf{2}}\mathbf{eV}^{-\mathbf{1}}$</tex> which could be related to the Schottky/dielectric interface.