No abstract

This article presents the study of the electrochemical deposition of zinc oxide from the non-aqueous solution based on dimethyl sulfoxide and zinc chloride into the porous silicon matrix. The features of the deposition process depending on the thickness of the porous silicon layer are presented. It is shown that after deposition process the porous silicon matrix is filled with zinc oxide nanocrystals with a diameter of 10-50 nm. The electrochemically deposited zinc oxide layers on top of porous silicon are shown to have a crystalline structure. It is also shown that zinc oxide crystals formed by hydrothermal method on the surface of electrochemically deposited zinc oxide film demonstrate ultra-violet luminescence. The effect of the porous silicon layer thickness on the morphology of the zinc oxide is shown. The structures obtained demonstrated two luminescence bands peaking at the 375 and 600 nm wavelengths. Possible applications of ZnO nanostructures, porous and continuous polycrystalline ZnO films such as gas sensors, light-emitting diodes, photovoltaic devices, and nanopiezo energy generators are considered. Aspects of integration with conventional silicon technology are also discussed

No abstract

Most power electronic modules are specifically designed for the customer and this entails intense labour during the production phase. The monolithic integration for power electronic devices in the form of power IC has not proven to be efficient, neither from a technical, nor from an economic point of view. In a typical high power module the power devices are assembled on a heatsink and driver, sensor and protection circuits are mounted on separate PCBs assembled to the power devices. This results in low performance and high cost. Higher integrated power modules are produced assembling power devices in die format onto a DCB (Direct Copper Bonding) substrate and interconnect them by wire bonding technique [1]. The relative driver, sensor and protection circuits are surface mounted on a separate PCB assembled with the former. Unfortunately, there are certain fundamental limitations to the above described packaging mainly due to wire bonding. In spite the fact that this technology has made enormous progress in recent years, it still limits the possibility of three dimensional packaging and puts major limits on creating low EMI and high frequency circuits. In this paper we present an already tested technology for compliant interconnection of power devices that overcomes the limitations of wire-bonding. In the development of this new technology, compatibility with wire-bonding has been strongly enforced to provide a solution that could be retrofitted to existing modules

In present work the investigation of the electrochemical and chemical hydrothermal deposition processes of ZnO on silicon is presented. The influence of the electrochemical process parameters on the characteristics and morphology of the ZnO deposits is analyzed. Electrochemical deposition from non aqueous DMSO solutions on porous silicon buffer layer is also discussed. The details of the chemical hydrothermal deposition from the nitrate bath of high-quality ZnO crystals on silicon substrate are presented. It was shown that morphology and size of synthesized ZnO crystals depends on the temperature of the deposition bath. Differences between photoluminescence of electrochemically deposited ZnO thin films and hydrothermally synthesized crystals are shown. Electrochemically deposited ZnO films demonstrate defect-caused luminescence and hydrothermally grown ZnO crystals shows intensive exciton luminescence band in UV region. Hydrothermal deposition of high-quality ZnO crystals on the surface of electrochemically deposited ZnO seed layer with porous silicon buffer improves photoluminescence properties of the structure which is useful for optoelectronics applications. Possible applications of ZnO as gas sensors and photovoltaic devices are considered. Aspects of ZnO electrochemical deposition on bulk silicon and silicon-on-isolator wafers for integration purposes are discussed.