electron beam lithography tool for 3D-nanoscale extremely high frequency components

• Subject Area: Systems Engineering
• Term: Funded in 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 491044589

3D nanoscale structures are at the foundation of state-of-the-art and future electronic and photonic extremely high frequency components for the terahertz range. Besides the atomic precision "built into" epitaxial semiconductor growth processes, an orthogonal lithographic structuring process is required to minimize critical areas and volumes in nanoscale devices, in particular to suppress parasitic capacitance and to reduce access resistance. This holds true for traditional device topologies based on epitaxial layer deposition, but also for novel epitaxial structures such as nanowires an devices based on 2D-materials. The definition of e.g. nanoscale electrodes is needed, along with nanometer-scale placement accuracy. The department "Components for High Frequence Electronics (BHE)" at UDE researches nanoscale semiconductor materials and processes to realize "beyond-fmax" Terahertz devices, funded among other programs through the SFB/TRR 196 MARIE. The focus is on own semiconductor material development with highest electron mobility, in particular indium phosphide and related materials, and on transistors and RF diodes built from these materials in the department's cleanroom facility. Since the growth and structuring is tightly coupled in the research process, the installation of a high performance nanoscale lithography in the own facility is needed to reach the current and future research goals. The method of choice is electron beam lithography (EBL). Commercially available EBL tools exhibit the required < 10 nm resolution combined with a placement accuracy below 10 nm. Of high importance is the large depth of focus which is available in EBL, which allows for the processing of pre-structured and shapes of irregular height. When opting for 100 keV electron energy, the proximity error can be well corrected even for materials such as indium phosphide which exhibit relatively high backscattering. Five additional research groups in Duisburg have expressed a need for this lithographic instrument within the faculty of engineering and the faculty of physics, each researching state-of-the-art topics on the nanoscale with significant horizon. The five research groups take part in this proposal. A high synergetic effect in procuring a high-resolution EBL tool is therefore expected. The requested tool shall be installed in the cleanroom facility of UDE's Center for Semiconductor Technology, in a location particularly suited for high resolution lithography (with very low building vibrations, optimized airflow and low electromagnetic fields).

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Elektronenstrahllithografie für 3D-nanoskalige Höchstfrequenzbauelemente
• Instrumentation Group: 0910 Geräte für Ionenimplantation und Halbleiterdotierung
• Applicant Institution: Universität Duisburg-Essen
• Leader: Professor Dr. Nils Weimann