A new approach is described for mounting microcrystals of biological macromolecules for cryocrystallography. The sample mounts are prepared by patterning thin polyimide films by standard microfabrication techniques. The patterned structures contain a small hole for the crystal connected to a larger hole via a drainage channel, allowing removal of excess liquid and easier manipulation in viscous solutions. These polyimide structures are wrapped around small metal rods. The resulting curvature increases their rigidity and allows a convenient scoop‐like action in retrieving crystals. The polyimide contributes minimally to X‐ray background and absorption, and can be treated to obtain desired hydrophobicity or hydrophilicity. The new mounts are fully compatible with existing automated sample‐handling hardware for cryocrystallography. Their potential advantages include completely reproducible sample hole sizes to below 10 µm; accurate and reproducible sample positioning and good sample‐to‐mount contrast, simplifying alignment; more convenient manipulation of small crystals; easier removal of excess liquid and reduced background scatter; reduced thermal mass and more rapid flash‐cooling; and easy design customization and mass production. They are especially well suited to data collection from the smaller crystals produced in high‐throughput crystallization trials, and are suitable for automated crystal retrieval. They should be more generally useful for X‐ray data collection from small organic and inorganic crystals of all types.

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In this paper the DC and switching performance of 600V Si, SiC and GaN power devices using device simulation. The devices compared are Si superjunction MOSFET, Si field stop IGBT, SiC UMOSFET and GaN HEMT.

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