High conversion rates are achieved in an analog to digital converter by tailoring the substrate type to specific operational elements of the converter. Embodiments place sample and hold processing circuitry on a substrate type having properties that allow for faster processing at high sampling/clock frequencies. Other operational elements of the converter are constructed on at least one other substrate type in keeping with the remainder of the circuitry for which the converter is being implemented. The sample and hold substrate may be implemented on any material which is capable of faster processing, such as silicon germanium, gallium arsenide, silicon bipolar, BiCMOS, and the like. Other portions may be implemented on a more CMOS substrate. Such systems and methods are able to implement analog-to digital conversion for broadband signals at high speeds without the need for extensive timing compensation, while also avoiding problems due to noise from further digital processing circuitry.