High-speed optoelectronic IC for multi-standards of optical storage system

Abstract

The conventional scheme of optical pick-up unit (OPU) should require two or three optoelectronic integrated circuits (OEICs) to cover triple-wavelength λ =780nm, 650nm and 405nm). In order to reduce cost and waste of resources, onechip solution of the OEIC is required. In this paper, the OEIC is designed which can cover triple-wavelength and three optical storage standards which are compact disk (CD), digital versatile disk (DVD) and Blue-Ray. The OEIC has dualarrays of photodiodes because focus of laser is varied depending on wavelength. One of arrays senses the laser of λ =780nm and another senses the lasers of λ =650nm and λ =405nm. For low power consumption and small die area, one wideband transimpedance amplifier (TIA) is used for two photodiodes which are for CD and DVD or Blue-Ray, respectively. And two small size switches are included to select photodiodes. The PIN fingerdiode with N+ fingercathode is integrated to guarantee high performances for λ =405nm and 650nm. And the isolation area between adjacent photodiodes is made by floated P+ implant for reducing power-loss. The measured cutoff bandwidth of the OEIC is 210MHz for λ =405nm. The OEIC is fabricated in a 0.6- μm BiCMOS technology and dissipates 150mW for a single supply voltage of 5V. The active area is 1.4x1.2mm 2 .