A comparison of CCD and CID detection for atomic emission spectroscopy

The performances of two classes of charge transfer device detectors-the charge-coupled device and the charge injection device-are compared for atomic emission spectroscopy. For these studies, a direct current plasma source is employed with an echelle spectrograph having a spectral image size matched to the format of these array detectors. In a clean matrix, both detectors yield good detection limits. In more complex matrices, blooming, or the spilling of excess photogenerated charge from the regions of the detector which are overexposed, greatly limits the utility and sensitivity of the charge-coupled device for atomic emission spectroscopy. Several methods to improve the performance of charge-coupled device detectors are described, including preliminary work using an antiblooming charge-coupled device. The charge injection device detector is found to be highly resistant to blooming and is able to analyze complex mixtures with little to no loss in sensitivity.