High-speed visualization of metal oxide precursor in multiphase AC arc during nanoparticle formation

Recently much interest has been devoted to Si-based heteroepitaxy, and in particular, to the SiGe/Si system. This is mostly for economical reasons: Si-based technology is much more advanced, is widely available, and is cheaper than GaAs-based technology. SiGe opens the door to the exciting (and lucrative) area of Si-based high-performance devices, although optical applications are still limited to GaAs-based technology. Strained SiGe layers form the base of heterojunction bipolar transistors (HBTs), which are currently used in commercial high-speed analogue applications. They promise to be low-cost compared to their GaAs counterparts and give comparable performance in the 2-20-GHz regime. More recently we have started to investigate the use of relaxed SiGe layers, which opens the door to a wider range of application and to the use of SiGe in complementary metal oxide semiconductor (CMOS) devices, which comprise strained Si and SiGe layers. Some recent successes include record-breaking low-temperature electron mobility in modulation-doped layers where the mobility was found to be up to 50 times better than standard Si-based metal-oxide-semiconductor field-effect transistors (MOSFETs). Even more recently, SiGe-basedp-type MOSFETS were built with oscillation frequency of up to 50 GHz, which is a new record, in anyp-type material for the same design rule.

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A metal oxide adhesion layer prepared with water based coating solution for wet Cu metallization of glass interposer

International Symposium on Microelectronics ◽

10.4071/isom-2015-wp21 ◽

2015 ◽

Vol 2015 (1) ◽

pp. 000365-000369 ◽

Cited By ~ 2

Author(s):

Zhiming Liu ◽

Sara Hunegnaw ◽

Hailuo Fu ◽

Jun Wang ◽

Tafadzwa Magaya ◽

...

Keyword(s):

Metal Oxide ◽

High Frequency ◽

Metal Layer ◽

Flat Glass ◽

Adhesive Layer ◽

Adhesion Layer ◽

Coating Solution ◽

Glass Substrates ◽

Oxide Precursor ◽

Oxide Adhesion

Inorganic interposers made of glass are attractive for advanced high frequency applications and ultra- fine line patterning technology. Because glass combines a couple of benefits like large form factor, good coefficient of thermal expansion (CTE) matching to silicon, smooth surface and a low dielectric constant and loss tangent. Recently much progress has been made with respect to glass electrical and physical properties. This allows for handling of thin glass sheets down to 100 μm in a typical PCB panel format. Also advances have been made in the area of laser drilling allowing aspect ratio up to 1:10 for 25 μm diameter of through glass via (TGV). Another major challenge is the cost competitive and reliable metallization of smooth glass, a critical prerequisite for the use of glass substrates in the electronic packaging market. Plated copper does not adhere directly to glass. Sputtering technology typically also requires a 50 nm thick adhesion promoting metal layer (like Ti) before copper can be seeded. This metal layer could not be etched together with the copper and needs to be removed between traces by etching in an additional step. A volatile flammable solvent based metal oxide precursor coating solution has been used to make an adhesive metal oxide layer by a modified sol-gel process. To prevent potential safety issue for mass production water based metal oxide precursor coating solution so called VitroCoat GI W has been developed. The VitroCoat GI W solution can be dip-coated on flat glass surface and TGVs followed by sintering to form an ultrathin metal oxide adhesion layer (about 10nm). The thin adhesive layer enables electroless and electrolytic copper plating directly onto glass substrates without changing any of the glass properties or impacting high frequency performance. The thin metal oxide adhesive layer is non-conductive and can be easily removed from the area between circuit traces. This paper will focus on the coating uniformity and capability of VitroCoat GI W on flat glass surface and TGVs and the adhesion of wet chemical metallization on glass interposer. This adhesion layer can be used for copper fine line patterning on glass and radio frequency (RF) device fabrication.

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A high-speed silicon optical modulator based on a metal–oxide–semiconductor capacitor

Nature ◽

10.1038/nature02310 ◽

2004 ◽

Vol 427 (6975) ◽

pp. 615-618 ◽

Cited By ~ 1045

Author(s):

Ansheng Liu ◽

Richard Jones ◽

Ling Liao ◽

Dean Samara-Rubio ◽

Doron Rubin ◽

...

Keyword(s):

Metal Oxide ◽

High Speed ◽

Metal Oxide Semiconductor ◽

Oxide Semiconductor ◽

Optical Modulator ◽

Metal Oxide Semiconductor Capacitor

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Vertical Field Emission Air-Channel Diodes and Transistors

Micromachines ◽

10.3390/mi10120858 ◽

2019 ◽

Vol 10 (12) ◽

pp. 858 ◽

Cited By ~ 3

Author(s):

Wen-Teng Chang ◽

Hsu-Jung Hsu ◽

Po-Heng Pao

Keyword(s):

Metal Oxide ◽

Atmospheric Pressure ◽

High Speed ◽

Ambient Pressure ◽

Electron Flow ◽

Mean Free Path ◽

Oxide Semiconductor ◽

Radiation Environment ◽

Reduced Pressure ◽

Transport Distance

Vacuum channel transistors are potential candidates for low-loss and high-speed electronic devices beyond complementary metal-oxide-semiconductors (CMOS). When the nanoscale transport distance is smaller than the mean free path (MFP) in atmospheric pressure, a transistor can work in air owing to the immunity of carrier collision. The nature of a vacuum channel allows devices to function in a high-temperature radiation environment. This research intended to investigate gate location in a vertical vacuum channel transistor. The influence of scattering under different ambient pressure levels was evaluated using a transport distance of about 60 nm, around the range of MFP in air. The finite element model suggests that gate electrodes should be near emitters in vertical vacuum channel transistors because the electrodes exhibit high-drive currents and low-subthreshold swings. The particle trajectory model indicates that collected electron flow (electric current) performs like a typical metal oxide semiconductor field effect-transistor (MOSFET), and that gate voltage plays a role in enhancing emission electrons. The results of the measurement on vertical diodes show that current and voltage under reduced pressure and filled with CO2 are different from those under atmospheric pressure. This result implies that this design can be used for gas and pressure sensing.

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