Abstract: A thermal picture synthesis device (1) of multi-layer construction has a resistor element (3) spaced from a semi-conductor substrate layer (2). The resistor element (3) is made of titanium or Ni-chrome. A drive element layer (4) is provided either in or attached to the substrate layer (2) for the resistor element (3). By placing the drive element layer parallel to and spaced from the resistor element (3) it is possible to pack a plurality of resistor elements (3) into a side by side adjacent array with a high fill factor or packing density and this coupled with the use of titanium or Ni-chrome for the resistor elements (3) and the spacing of these elements from the semi-conductor substrate (2) allows the device to operate at a higher apparent temperature than is conventional.

Abstract: A method of forming through-holes in a multi-level interconnect system in which a layer of photo-resist is spun over a masking layer prior to mask-etching so that when the photo-resist is exposed and developed some remains in the bottom of through holes formed in the surface layer so as to protect the base layer from the mask-etching agent.

Abstract: A thermal image producing device comprising an array of separately addressable thin-film resistors on a substrate with a heat sink at its near face and, so as to render the heat flux flowing through the substrate into the heat sink spatially and temporarily uniform, e.g. to avoid smearing, an array of compensating resistors, each beneath a respective one of the image producing resistors and separated therefrom by an insulating layer. Each compensating resistor is controlled so that, it and its associated image producing resistor together, produce a uniform total heat flux.