Spatial Pixel Crosstalk In A Charge-Injection Device

An optical multichannel detector system based on a charge-injection device (CID) sensor has been designed and constructed. This system is intended for use in a variety of spectroscopic studies, including atomic emission spectrometry (AES), in the ultraviolet to near-infrared spectral region. A General Electric Co. CID11 B was selected as the sensor because preliminary research indicated that this device has excellent characteristics for detection of the very wide dynamic range signals encountered in AES. During initial characterization of this detection system, a phenomenon was observed in which the signal obtained from reading a pixel of the array was affected by the quantity of charge in orthogonally located pixels. Investigations indicate that this spatial crosstalk effect is not caused by charge migration among pixels ("blooming") as in many other types of imaging detectors. Instead, the source of crosstalk for the CID11B is capacitive coupling of charge-collection and charge-sensing electrodes during the readout process. Because no charge migration is involved with this process, crosstalk in a CID can be corrected by simple algorithms, which are described.