Transistor, thin film high voltage

For high information-content displays, active-matrix (AM) pixel addressing provides improved display performance and reduced power consumption. In active matrix addressing each individual pixel is controlled by one or more thin-film transistors (TFTs). To date, most AM OLED displays have used polysilicon TFTs as the active elements, because they can provide sufficient current at low voltages and acceptable device dimensions, and they are capable of integrated drive electronics... 

Semi-insulating polycrystalline silicon (SIPOS) is found in many applications, including the electrical passivation of high-voltage planar devices, emitters in heterojunction transistors, and thin-film silicon solar cells on cheap foreign substrates. SIPOS is usually deposited by CVD onto a Si substrate. The composition of the SIPOS SiOx Aim varies from x = 0 (polycrystalline or amorphous Si) to X = 2 (Si02). The untreated film consists of a nonrandom mixture of Si and Si02 and relatively small amounts of an intermediate oxide of SiOi A (A = 0.14) [75, 76]. 

One way in which the sharpness of an LCD can be increased is to fabricate the display with an active device such as a thin film transistor at each pixel. This is shown in Figure 13.12, where it can be seen that the voltages are applied to the electrodes and transistor in such a way that the response is determined mostly by the transistor rather than the display itself A properly designed transistor can increase the sharpness of a LCD a great deal, allowing for highly multiplexed displays. Such an active matrix LCD is used in laptop computers (see Plate 8). 

Identification of solution processable dielectric materials is also crucial to the commercial application of high performance, low cost, organic thin film field effect transistors. The fiiin dielectric films must be pinhole fiee and have a high breakdown voltage and good long-term stability. To permit fire use of plastic substrates in these devices, it is also desirable that the films can be formed at... 

One of the most important necessary conditions in recent LCD such as thin film transistor and super twisted nematic modes is to have higher voltage holding ratio Ry > 95%) even in a high-temperature... 

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