Physics:Pixel detector

A semiconductor detector made of wafers with very small rectangular two-dimensional detector elements, pads, but of typical linear size of less than a mm. A large number of such detector elements on a surface ensures high spatial resolution in two coordinates, in the plane of the wafer. The precision achieved makes pixel detectors ideal candidates for vertex chambers, e.g. in experiments aimed at the detection of heavy-flavour particles, see Hallewell96. The readout of the very large number of channels is not without problems; it is usually done capacitively; see Heijne89.