Thin-film resistor fabrication

Process Control of Vacuum-Deposited Nickel-Chromium for the Fabrication of Reproducible Thin-Film Resistors... 

In monolithic Integrated circuit technology, all circuit elements are fabricated on, or within, a single crystal piece of semiconductor material by means of a sequential series of diffusion, photolithography and thin film processes. As a production method, generally where thin film resistors are required, the following process sequence Is defined ... 

Most of the experiments for detecting charged macromolecules with FEDs, reported in literature, have been realized using a transistor stmcture [11-36]. Recent successful experiments on the detection of charged biomolecules as well as polyelectrolytes with other types of FEDs, namely semiconductor thin film resistors [39-41], capacitive MIS [42] and EIS structures [43-50], have demonstrated the potential of these structures - more simple in layout, easy, and cost effective in fabrication - for studying the molecular interactions at the solid-liquid interface. A summary of results for the DNA detection with different types of FEDs is given in Table 7.1. 

If the subsequent assembly process calls for thermocompression or thermosonic wire bonding, plated copper under the wire-bond sites should be avoided. This can be accomplished by selectively plating the copper. When the adhesion layer is Nichrome or titanium-tungsten, then precision-deposited thin-film resistors can be fabricated. 

Riza et al. fabricated a three-terminal device for optical beam forming [6]. Figure 5.4 shows the top view of a thin film resistor-biased LC cylindrical lens, with electrical biasing resistors on the left and right sides of the active area. A spherical or elliptical lens can be formed by the appropriate use of a cascade of two such LC cylindrical lenses with orthogonal lens axes. 

Of the mass-transfer dispensing methods, screen printing and stencil printing are the oldest and most widely used. Screen printing has been used for over 40 years in the electronics industry to apply thick-film conductors, resistors, and dielectrics in fabricating circuits on ceramic and plastic-laminate substrates. Screen printing is also used as a batch process for depositing electrically conductive and insulative adhesives to interconnect devices on thin-film and thick-film hybrid microcircuits. 

The cavity can be made of silicon, quartz, or glass substrates or any other appropriate materials. Because of the convenience of silicon micromachining techniques, silicon is commonly used to fabricate the cavity and flexible membrane. Normally a thin-film heating resistor is integrated onto one inner side of the cavity, with a flexible diaphragm wall sealing the opposite inner side of the small cavity. When an electrical current is passed through the resistor, the trapped fluid is heated to evaporate and expand. The expansion causes the flexible wall to flex outward. This outward flex movement is then used to close or open the flow. An SCE microactuator can function as a normally opened microvalve, which opens the channel in its normal... 

The method of deposition is what differentiates the hybrid circuit from other packaging technologies and may be one of two types thick film or thin film. Other methods of metallizing a ceramic substrate, such as direct bond copper, active metal brazing, and plated copper, may also be considered to be in the hybrid family, but do not have a means for directly fabricating resistors and are not considered here. Semiconductor technology provides the active components, such as integrated circuits, transistors, and diodes. The passive components, such as resistors, capacitors, and inductors, may also be fabricated by thick- or thin-film methods or may be added as separate components. 

Thin-fitmpassive components rely on deposition and photohthography to define conductive, resistive, and dielectric materials physically that produce a desired electrical response. Integrated resistors are fabricated by depositing and patterning a layer of thin-film or thick-film... 

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