AN EPITAXIALLY-GROWN CHARGE MODULATION DEVICE

A charge modulation device (CMD) has been fabricated in a p-type epita xial layer grown from the buried-channel silicon region of a charge-co upled device (CCD). Construction of the CMD directly above the CCD bur ied-channel and over the oxidized CCD transfer gates lowers the effect ive sense capacitance while providing isolation of the CMD source/drai n regions. Responsivity values of 28 and 66 mu V/e for feedback and no feedback conditions, respectively, were measured dynamically on test devices. Input-referred noise values of approximately four electrons r ms were calculated from noise spectral density measurements assuming a low-pass filter 3 dB cutoff frequency of 5 MHz and correlated double sampling.