Silicon dioxide

It is the dioxide form of silicon, SiO 2, occurring especially as quartz sand, flint, and agate: used usually in the form of its prepared white powder chiefly in the manufacture of glass, water glass, ceramics, and abrasives.

  • 30.2 Percent Efficiency – New Record for Silicon-based Multi-junction Solar Cell

    Wafer-bonded III-V / Si multi-junction solar cell with 30.2 percent efficiency. ©Fraunhofer ISE/A. Wekkeli

    Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with the Austrian company EV Group (EVG) have successfully manufactured a silicon-based multi-junction solar cell with two contacts and an efficiency exceeding the theoretical limit of silicon solar cells. For this achievement, the researchers used a “direct wafer bonding” process to transfer a few micrometers of III-V semiconductor material to silicon, a well-known process in the microelectronics industry. After plasma activation, the subcell surfaces are bonded together in vacuum by applying pressure. The atoms on the surface of the III-V subcell form bonds with the silicon atoms, creating a monolithic device.

  • IHP presents the fastest silicon-based transistor in the world

    The cross section shows a SiGe HBT of the latest generation, recorded by a TEM. The measurement curves are used to determine the transit frequency and the maximum oscillation frequency. © IHP 2016

    Frankfurt (Oder)/San Francisco. Scientist Dr. Bernd Heinemann of IHP – Innovations for High Performance Microelectronics will present results on silicon-germanium heterobipolar transistors (SiGe HBTs) developed in Frankfurt (Oder) on the “International Electron Devices Meeting” (IEDM) in San Francisco. His contribution titled “SiGe HBT with fT/fmax of 505 GHz/720 GHz “ presents speed parameters that set new standards for silicon transistors. “To present at IEDM is a valuable conclusion of the project ‘DOTSEVEN’, funded by the European Union. Together with Infineon and twelve other project partners from a total of six countries, the four-year project focused on developing SiGe HBTs with a maximum oscillation frequency, which is also referred to as fmax, of 0.7 THz,” says Dr. Bernd Heinemann, project manager at IHP.

  • Silicon solar cell of ISFH yields 25% efficiency with passivating POLO contacts

    Monocrystalline 25%-silicon solar cell with POLO-contacts for both polarities on the rear side of the solar cell. ISFH

    The Lower Saxon‘ Institute for Solar Energy Research Hamelin (ISFH) achieved a solar cell efficiency of 25 % in collaboration with the Institute of Electronic Materials and Devices (MBE) of the Leibniz Universität Hannover. This high efficiency was accomplished with passivating "poly-Si on oxide" contacts (POLO) for both polarities, which avoid the otherwise high recombination beneath the metal contacts. The Lower Saxon‘ Institute for Solar Energy Research Hamelin (ISFH), an affiliated institute of the “Leibniz Universität Hannover” in collaboration with the Institute of Electronic Materials and Devices (MBE) of the “Leibniz Universität Hannover” achieved a solar cell efficiency of 25 %. This result was confirmed by DAkkS-accredited independent calibration laboratory ISFH CalTeC and presented at the Asian conference PVSEC-26 in Singapore.