Metal-insulator-semiconductor devices diode

A two colour infrared detector is described in US-A-5300777 which for each detector element comprises a heterojunction diode and a metal-insulator-semiconductor device. 

The use of semiconducting conjugated polymers as an electro-active material in microelectronic devices is a rapidly growing area. Burroughes et al. [248] reported the first examples of high-performance Schottky diodes, metal-insulator semiconductor (MIS) diodes and the MIS-field effect transistor (MISFET) structure involving conjugated polymers. 

A Schottky diode is always operated under depletion conditions flat-band condition would involve giant currents. A Schottky diode, therefore, models the silicon electrolyte interface only accurately as long as the charge transfer is limited by the electrode. If the charge transfer becomes reaction-limited or diffusion-limited, the electrode may as well be under accumulation or inversion. The solid-state equivalent would now be a metal-insulator-semiconductor (MIS) structure. However, the I-V characteristic of a real silicon-electrolyte interface may exhibit features unlike any solid-state device, as... 

Figure 4.15. Top Cross section of a MISS diode. The device can be regarded as a reverse-biased metal-insulator-semiconductor diode in series with a for-ward-biased n-p Junction. It then exhibits two stable states separated by an unstable negative resistance region. Bottom Current-voltage characteristics for a GaAs-(j -TA MISS device. The LB film thickness is approximately 9 nm...

Due to the technological importance of metal-insulator-semiconductor (MIS) devices, understanding of the nature of their electrical characteristics such as current-voltage (1-V) and tunnel magnetoresistance (TMR) is of great interest. Unless intentionally fabricated, a silicon Schottky diode possesses a thin interfacial oxide layer between the metal and the semiconductor. Additionally, a density of interface states is always generated at the boundary between the semiconductor and insulator. 

The most common detector for AES is the photomultiplier tube (see p. 174). An alternative approach for the detection of multielement (multiwavelength) information is the charged-coupled device (CCD). A CCD is essentially an array of closely spaced metal-insulator-semiconductor diodes formed on a wafer of semiconductor material. Incident light striking the CCD is converted into an electrical signal. 

ZnO, and heterostructure devices. Among the devices, light emitters, microcavities, optically pumped lasers, photodiodes, metal-insulator-semiconductor diodes, field-effect transistors, transparent conducting oxides, and transparent thin-fihn transistors based on ZnO, piezoelectric devices in the form of surface acoustic wave devices, and gas and biosensor followed by solar cells cap the discussion. 

We have found that the polymer prepared in this way is very well suited for use in semiconductor device structures in which a semiconductor of one carrier type only is required (unipolar devices). The polymer as prepared is extrinsically doped with p-type carriers, to a concentration in the range lO to 10 8 cm 3, and these dopants are not readily mobile under the applied electric fields within these structures. We have made and measured Schottky-barrier diodes, MIS (Metal Insulator Semiconductor) diodes and MISFETs (MIS Field Effect Transistors), and it is the results of these investigations, some of which are published elsewhere [11-17], which are presented in the present chapter. 

The ion controlled diode was an initial attempt to isolate the active electronics from the chemical solution by producing a metallic-like via that allows the isolation of the chemically sensitive region from an area where electronic components could be deposited (41,42). However, the limited precision of the non-standard microfabrication techniques made this process difficult and costly. Since this device is still essentially a capacitive membrane-insulator-semiconductor structure like the chemfet, the same problems of hermetic isolation of the gate remain. 

The simplest and most widely used model to explain the response of organic photovoltaic devices under illumination is a metal-insulator-metal (MIM) tunnel diode [55] with asymmetrical work-function metal electrodes (see Fig. 15-10). In forward bias, holes from the high work-function metal and electrons from the low work-function metal are injected into the organic semiconductor thin film. Because of the asymmetry of the work-functions for the two different metals, forward bias currents are orders of magnitude larger than reverse bias currents at low voltages. The expansion of the current transport model described above to a carrier generation term was not taken into account until now. 

The problems of rms addressing of liquid crystal devices can be circumvented by incorporating a semiconductor switch at each pixel of the display. The most usual architecture uses a field effect transistor as the switch [69], while other active components such as diode networks [70] and MIM (metal-insulator-metal) switches [71] have also been used (Fig. 18). The semiconductor material is usually amorphous silicon, which can be deposited and processed at temperatures compatible with a glass substrate. Polycrystalline silicon and other semiconductors, especially cadmium selenide, are also used in special applications such as those requiring very small pixel geometries and, by virtue of their higher carrier mobility, offer the... 

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