A wedge shape Si LED is designed and fabricated with 0.35 μm double-grating standard CMOS technology. The device structure is based on the N-well-P+ junction. The P+ has a wedge shape and is surrounded by the N-well. The micrographs of Si LEDs' emitting and layout are captured. The I-V characteristic and spectra of the Si LED are tested. Under room temperature and backward bias, its radiant luminosity is 12 nW at 100 mA, and the wavelength of the emitting peak is located at 764 nm.
The wedge-shaped and leaf-type silicon light-emitting devices(LED)are designed and fabricated with the Singapore Chartered Semi Inc.'s dual-gate standard 0.35μm CMOS process.The basic structure of the two devices is N well-P+ junction.P+ area is the wedge-shaped structure,which is embedded in N well.The leaf-type silicon LED device is a combination of the three wedge-shaped LED devices.The main difference between the two devices is their different electrode distribution,which is mainly in order to analyze the application of electric field confinement(EFC).The devices' micrographs were measured with the Olympus IC test microscope.The forward and reverse bias electrical characteristics of the devices were tested.Light measurements of the devices show that the electrode layout is very important when the electric field confinement is applied.
A sensitivity design method for a CMOS optoelectronic integrated circuit (OEIC) receiver is reported. The receiver consists of a regulated cascade (RGC) transimpedance amplifier (TIA) and a double photodiode (DPD) detector. The noise and sensitivity of the receiver are analyzed in detail. The noise mainly comes from the thermal noise of resistors and the flicker noise of MOSFETs. The relationship between noise and receiver sensitivity is presented. The sensitivity design method for the receiver is given by a set of equations. The OEIC receiver was implemented in a CSMC 0.6μm standard CMOS process. The measured eye diagram shows that the CMOS OEIC receiver is able to work at bit rates of up to 1.25GB/s and the sensitivity is - 12dBm.
A monolithically integrated optical receiver, including the photodetector, has been realized in Chartered 0.35μm EEPROM CMOS technology for 850 nm optical communication. The optical receiver consists of a differential photodetector, a differential transimpedance amplifier, three limiting amplifiers and an output circuit. The experiment results show that the receiver achieves an 875 MHz 3 dB bandwidth, and a data rate of 1.5 Gb/s is achieved at a bit-error-rate of 10-9. The chip dissipates 60 mW under a single 3.3 V supply.
The design and fabrication of a high speed, 12-channel monolithic integrated CMOS optoelectronic integrated circuit (OEIC) receiver are reported. Each channel of the receiver consists of a photodetector, a transimpedance amplifier,and a post-amplifier. The double photodiode structure speeds up the receiver but hinders responsivity. The adoption of active inductors in the TIA circuit extends the - 3dB bandwidth to a higher level. The receiver has been realized in a CSMC 0.6μm standard CMOS process. The measured results show that a single channel of the receiver is able to work at bit rates of 0.8- 1.4Gb/s. Altogether, the 12-channel OEIC receiver chip can be operated at 15Gb/s.
A high-bandwidth, high-sensitivity fully differential optoelectronic integrated receiver is implemented in a chartered 3.3 V standard 0.35μm analbg CMOS process. To convert the incident light into a pair of fully differential photo-currents, a novel fully differential photodetector is proposed, which is composed of two completely identical photodiodes. The mea- surement results show that the receiver achieves a 1.11 GHz 3 dB bandwidth and a -13 dBm sensitivity for a 10-12 bit error at 1.5 Gb/s data rate under illumination by 850 nm incident lights.
YU Chang-liang MAO Lu-hong XIAO Xin-dong XIE Sheng ZHANG Shi-lin
A wideband monolithic optoelectronic integrated receiver with a high-speed photo-detector,completely compatible with standard CMOS processes,is designed and implemented in 0.6μm standard CMOS technology.The experimental results demonstrate that its performance approaches applicable requirements,where the photo-detector achieves a -3dB frequency of 1.11GHz,and the receiver achieves a 3dB bandwidth of 733MHz and a sensitivity of -9dBm for λ=850nm at BER=10-12.