VLSI semiconductor electronics

FIGURE 30 Schematic of horizontal and vertical integration of polymeric modulators with VLSI semiconductor electronics. 

Recently, optical loss due to optical mode size mismatch between polymer EO waveguide modes and silica frber modes have been dramaticaUy reduced exploiting reactive ion etched tapered transitions (5). This achievement together with the demonstration of integration of polymeric electro-optic circuitry with VLSI semiconductor electronics (6) and very large polymeric modulator bandwidths (7) represent dramatic advances in the utilization of lymeric electro-optic materials. 

Electronic industry Thin films for insulating barriers or masks for etching processes XY machine tables for VLSI semiconductor manufactures ... 

Photoresists and electron-beam resists are the key to the success of VLSI electronic circuits. Without these resists, most electronic equipment would not exist. These polymers are spun onto the semiconductor and exposed to the circuit pattern leading to main chain scission or crosslinking. Subsequently, unpolymerised sections are removed. This process is employed either in wet or in dry conditions. This is known as the photolithographic process, which is part of the semiconductor fabrication technology. Further treatment includes diffusion of various semiconductor elements and metallisation for conduction lines. Layer by layer, the total package is developed. Current research is now directed toward finer features in the patterns and changes in the surface characteristics for subsequent layers. 

Dalton, L.R., A.W. Harper, A. Ren, E Wang, G. Todorova, J. Chen, C. Zhang, and M. Lee. 1999. Polymeric electro-optic modulators From chromophore design to integration with semiconductor VLSI electronics and silica fiber optics. Ind Eng Chem Res 38 8—33. 

The new mobile ion, such as sodium or potassium, tends to migrate to the p-n junction of the IC device where it picks up an electron and deposits as the correspondent metal on the p-n junction which destroys the device Chloride ions, even in trace amounts (in ppm level), could cause the dissolution of alxjminum metallization of complementary metal-oxide semiconductor (CMOS) devices Unfortunately, CMOS is likely to be the trend of the VLSI technology and sodium chloride is a common contaminant. The protection of these devices from the effects of these mobile ions is apparent. 

The methods for miniaturization of chemical and biosensors are based on an extension of VLSI fabrication techniques, however with a broader range of materials [1-6], The range of materials is beyond what is normal for IC electronic devices because additional functionality is needed. These materials include electrochemi-cally active metals with catalytic properties, conductive oxides, and high-temperature materials. Examples of metal oxides include Sn02, WO3, and Ti02, and other catalytic metals include Pt, Ru, Ir, Pd, and Ag needed for electrochemical sensors [7,8]. As the dimensions of semiconductor devices continue to move to smaller gate lengths, nanoscale fabrication techniques are now developed. Hence, stmctures for sensors... 

Very large scale integration (VLSI) technology and electronic devices Carbides and diborides as field and thermal emitters, TiN as a diffusion barrier in metallization to Si semiconductors, resistive thermoconductive humidity sensors with TaN film, and Josephson tunnel junctions with NbN film. 

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