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Silicon wafers with high aspect ratio surface microstructures, prepared by deep reactive ion etching and coated with a protective layer, are replicated into a Zr-based bulk metallic glass. Therefore, a new process route called hot mold quenching is developed. In this process, the bulk glass-forming alloy and the mold are heated to a temperature of 1350 K to allow complete wetting of the microstructured silicon mold by the melt. After a few seconds, the surface microstructures of high aspect ratio are filled by the melt completely. Mold and melt are then quenched together at a rate of 20 K/s to prevent crystallization in the Zr-Cu-Ni-Al-Ti melt. Subsequently, the wafer is removed by wet etching. Structures of 20 µm height, 8 µm width and a spacing of 1 µm have successfully been replicated into the metallic glass. Tools out of this material have a high strength, a high elastic limit and a good corrosion resistance, and meet the requirements for injection molding of polymers ideally.

In a thermoelectric generator (TEG), hundreds of individual couples of two thermoelectrically dissimilar materials are electrically connected in series, but thermally in parallel within a given heat flux. Thus, the devices generate a few 10s of mW and may, for example, be used in wireless sensor applications. Apart from highly integrated costly batch fabricated micro TEGs for niche applications, commercially available Peltier/TEG modules are assembled manually from bismuth telluride (Bi 2 Te 3 ) blocks. The present work aims at new designs of metal (nickel-copper) and semiconductor based TEGs. The proposed combination of electrochemical deposition with known printed circuit board (PCB) techniques will facilitate industrial mass-production. Our first fully packaged prototype consists of 29.5 Ni/Cu couples per cm2 at an effective area of 13 cm2. At a temperature drop of 36 K across the packaged device, it generates an output power of 450 µW (∼27 nW/K2/cm2). The thermoelectric characterization is performed in a 200 W test setup.

Survival of pancreatic cancer is improved by surgery and is related to R0 resection. An accurate diagnosis and a careful staging are mandatory. Differential diagnosis must be estabilished between the different pancreatic lesions as carcinoma, chronic pancreatitis, cystic or endocrine neoplasms. Endoscopic ultrasound (EUS) is the best technique for diagnosis and allows cytological examination by fine needle aspiration (FNA). Preoperative resectability is defined by EUS in borderline tumors. EUS is a useful procedure for the surgical strategy of pancreatic cancer.