Photolithographic patterning

This type of coil was prepared from copper cladded printed circuit board material by applying photolithographic techniques. The p.c. board material is available with difierent copper thicknesses and with either a stiff or a flexible carrier. The flexible material offers the opportunity to adapt the planar coil to a curved three dimensional test object. In our turbine blade application this is a major advantage. The thickness of the copper layer was chosen to be 17 pm The period of the coil was 100 pm The coils were patterned by wet etching, A major advantage of this approach is the parallel processing with narrow tolerances, resulting in many identical Eddy current probes. An example of such a probe is shown in fig. 10. 

OLEDs are obviously able to produce light with virtually every color in the CIE chromaticity diagram but the optimum inexpensive method to manufacture a pixeiatcd full color display is not yet established. The difficulty lies in patterning OLED materials with standard photolithographic methods. Five schemes to achieve color have been suggested, as illustrated schematically in Figure 13-19. 

This technique is used to transfer a computer-generated pattern onto a substrate. Here, a film of photoresist is spin-coated onto the substrate and exposed to UV light through a photolithographic mask the light exposure transfers the desired pattern to the photoresist. Depending on whether the resist material is positive or negative , the photoresist... 

The fabrication method generates functional elements via anisotropic etching of high-quality semiconductor wafers, referred to as mother wafers.13 17 25 The process begins with photolithographic definition of patterns... 

The high selectivity of wet etchants for different materials, e.g. Al, Si, SiOz and Si3N4, is indispensable in semiconductor manufacturing today. The combination of photolithographic patterning and anisotropic as well as isotropic etching of silicon led to a multitude of applications in the fabrication of microelectromechanical systems (MEMS). 

The manufacture of a photonic crystal requires extreme process control because a deviation from perfect periodicity in the order of a few percent of the wavelength worsens the optical performance. Macroporous silicon is a potential candidate for the realization of such structures because of its photolithographic patterning. The precision of the macroporous structures is reflected in the transmission measurements along the T-M and T-K directions, which exhibit a photonic band-gap centered at 5 pm, as shown in Fig. 10.16. For measurement the macroporous... 

Scheme 2 Photolithographic process for preparing patterned hyperbranched grafts of poly(acrylic acid)...

As insulation between the coil and the magnetic core, a hard-cured (to 200°C) photoresist insulator is patterned. It is a novolak polymer or polyimide about 5 fim thick, which is popular for its high insulator and photolithographic properties. This provides electrical insulation as well as a planar surface for subsequent deposition of copper cods. 

To determine the effect of spot size, various photolithographic masks were used to create arrays of square patterns at spot widths from 80 to 1145 p. The Kjjpp ( 1 standard deviation) did not vary over the spot size range of 80 to 1145 p under constant flow conditions at fixed levels of antigen concentration, and little effect of variation in spot size was noted on mean binding. 

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