Practical Electron Microscopy and Database

Chapter/Index: Introduction | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Appendix

Electron Microscopy Sample Preparation of SiC (Silicon Carbide) Materials

Table 0013. Electron microscopy sample preparation of SiC (Silicon Carbide) materials. EM sample SEM Sample Preparation  Commercially available 4H-SiC MOSFET samples were mounted onto 12.5mm aluminum SEM specimen holders and coated with a 20nm gold layer for conductivity. FIB-SEM  Cross sections were milled at a 90° angle using a ZEISS Crossbeam 550 FIB-SEM at 30kV. Imaging was performed at a 54° tilt using an in-column secondary electron detector with the electron beam current set at 2nA. An optimal beam voltage of 2.0kV was selected for tomography based on qualitative analysis of contrast. (see page657) Platinum and Carbon Layer Deposition  A 40 x 60 x 1µm³ platinum layer was deposited using ion beam deposition. FIB cuts were made into the platinum layer, followed by an ion beam-deposited carbon layer to stabilize the region for milling. Trench Milling  A large trench was milled in front of the deposited layers at 30kV and 30nA for easier access to the region of interest. The cross section was then polished with a 30kV, 7nA ion beam, followed by finer slicing at 30kV and 3nA. EBIC Measurement  A beveled cross section was prepared by cutting across 21 adjacent gates of the MOSFET. The EBIC measurement setup involved using an incident ion beam of 30kV and 30nA to create a rectangle at a specific angle for imaging. The EBIC measurements were taken using a Kleindiek Nanotechnik PS8e Prober Shuttle with an EBIC amplifier. Reference [1]       [1] Heiko Stegmann, Greg Johnson, David Taraci, Andreas Rummel, 3D Visualization and Characterization of SiC MOSFET Junctions Using EBIC and FIB-SEM Tomography, access in 2023.