I. Introduction
Usually, silicon optoelectronic integrated circuits (OEICs) suffer from slow carrier diffusion of photogenerated carriers in the integrated photodiodes due to the low light absorption coefficient of silicon in the red and near-infrared spectral range, and, as a consequence, due to light penetration beyond the space-charge/drift region, due to doping levels in excess of in silicon chip processing leading to rather thin space-charge regions and due to a low supply voltage. Many integrated photodiodes achieve bandwidths lower than several tens of megahertz [1], [2]. In bipolar and BiCMOS processes, several hundred megahertz can be reached, with the drawback of a low responsivity of about 0.07 A/W [3]. PIN photodiodes with wide low-doped drift regions and high-quantum efficiency can be integrated, but at the cost of process modifications [4]. Here, we present a monolithically integrated OEIC which incorporates a charge pump used as a voltage up-converter (VUC) to enhance the speed of integrated photodiodes without needing a second external higher supply voltage.