Abstract: For large-volume optoelectronics applications, the low cost, manufacturability and reliability of silicon MOSFET technology are advantageous. In addition, silicon photodetectors operate quite efficiently at the 0.8 $mu@m wavelength of economical AlGaAs light sources. In this letter, we report on a silicon-based monolithic optical receiver. A symmetric transimpedance preamplifier was designed and simulated for depletion-mode NMOS with L$-gate$/ $EQ 1 $mu@m and V$-T$/ $EQ $MIN@0.1 V. The symmetric circuit provides insensitivity of dc bias point to FET threshold voltage deviation. The silicon photodiode is a planar p-i-n structure with a diameter of 20 $mu@m. The fabrication of the integrated lightwave receiver was carried out on a nominally undoped p-type Si substrate. The p-i-n photodetector is fabricated directly on the high-resistivity substrate so that the thickness of the detector depletion layer is approximately equal to the optical absorption length of 0.8 $mu@m light in silicon. A more heavily-doped p-well was formed for the NMOSFET fabrication. The silicon photodiodes have a dark current of 16 nA at 5 V, a break-down voltage of greater than 40 V, and a zero-bias capacitance of 40 fF. The external quantum efficiency of the photodiode at 870 nm is approximately 60% at 5 V without an AR coating, and the bandwidth of the device is approximately 1.5 GHz. Frequency response evaluation of the receiver indicates a bandwidth of 250 MHz with open eye diagrams demonstrated at 350 MBit/s. !7
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