X-ray diffraction methods for determining alloy composition and mismatch have been used for many years by measuring the separation of peaks in a high-resolution diffractogram. This method can still be used, but not for layer thicknesses below 1–2 μm. The diffractogram may appear simple to interpret, for example, two diffraction peaks from a single layer on a substrate, but simple measurement of peak separation can lead to significant errors in determining the mismatch and hence alloy composition. This paper gives examples of peak shifting with thin layers and shows how, by simulating the diffraction profiles, a reliable determination of mismatch, and hence alloy composition can be made.

A scalable manufacturing process for fabricating active-matrix backplanes on low-cost flexible substrates, a key enabler for electronic-paper displays, is presented. This process is based on solution processing, ink-jet printing, and laser patterning. A multilayer architecture is employed to enable high aperture ratio and array performance. These backplanes were combined with E Ink electrophoretic media to create high-performance displays that have high contrast, are bistable, and can be flexed repeatedly to a radius of curvature of 5 mm

We have developed a scalable manufacturing process for active matrix displays compatible with low temperature plastic substrates and have applied this technology to the fabrication of flexible SVGA display backplanes. We combined these backplanes with E Ink® Imaging Film to produce 100 PPI SVGA (800×600 pixel) displays exhibiting grey scale and with a high aperture ratio. Power consumption is zero in between image changes. Flexible high information content e‐paper displays will change the way in which information is conveyed by enabling lightweight, robust e‐reader devices.

2D image sensor arrays made with a-Si devices on glass over large area are of considerable interest as document scanners and in medical applications. We have made a test array containing a-Si NIP diodes for both the sensors and the active matrix switching devices. The issues of vertical crosstalk and image lag are discussed in relation to the device performance of the switching diode. The vertical crosstalk is controlled by the diode capacitance and the image lag by the high transient current in the device. We speculate that the transient current is a trap filling current in the deep states of the switching diode.

Multi-quantum-well (MOW) structures can be regarded as new materlals whose properties are determined by the well and barrier thicknesses 1, and Le and the well depth (which is composition dependent). Measurements of L,, L e and x are reported for 16 MQW samples grown by molecular beam epitaxy in the AI,Gal-x~s system. Results from x-ray diffraction, photoluminescence excitation spectroscopy and transmission electron microscopy are found to compare well with each other and with values predicted from MBE growth conditions.