Gallium Aluminum Arsenide/Gallium Arsenide Integrated Optical Repeater

A low threshold buried heterostructure laser, a metal-semiconductor field effect transistor (MESFET), and a photodiode, have for the first time, been monolithically integrated on a semi-insulating GaAs substrate. This integrated optoelectronic circuit (IOEC) was operated as a rudimentary optical repeater. The incident optical signal is detected by the photodiode, amplified by the MESFET, and converted back to light by the laser. The gain bandwidth product of the repeater was measured to be 178 MHz

Monolithic optoelectronic integration of a GaAlAs laser, a field-effect transistor, and a photodiode

A low threshold buried heterostructure laser, a metal-semiconductor field-effect transistor, and a p-i-n photodiode have been integrated on a semi-insulating GaAs substrate. The circuit was operated as a rudimentary optical repeater. The gain bandwidth product of the repeater was measured to be 178 MHz

A 3 Gb/s optical detector in standard CMOS for 850 nm optical communication

This paper presents a monolithic optical detector, consisting of an integrated photodiode and a preamplifier in a standard 0.18-/spl mu/m CMOS technology. A data rate of 3 Gb/s at BER <10/sup -11/ was achieved for /spl lambda/=850 nm with 25-/spl mu/W peak-peak optical power. This data rate is more than four times than that of current state-of-the-art optical detectors in standard CMOS reported so far. High-speed operation is achieved without reducing circuit responsivity by using an inherently robust analog equalizer that compensates (in gain and phase) for the photodiode roll-off over more than three decades. The presented solution is applicable to various photodiode structures, wavelengths, and CMOS generations

Demonstration of multi-channel 80 Gbit/s integrated transmitter and receiver for wavelength-division multiplexing passive optical network and fronthauling applications

The performance evaluation of a multi-channel transmitter that employs an arrayed reflective electroabsorption modulator-based photonic integrated circuit and a low-power driver array in conjunction with a multi-channel receiver incorporating a pin photodiode array and integrated arrayed waveguide grating is reported. Due to their small footprint, low power consumption and potential low cost, these devices are attractive solutions for future mobile fronthaul and next generation optical access networks. A BER performance of <10(-9) at 10.3 Gbit/s per channel is achieved over 25 km of standard single mode fibre. The transmitter/receiver combination can achieve an aggregate bit rate of 82.4 Gbit/s when eight channels are active

Integrated Photodiodes in Standard CMOS Technology for CD and DVD Applications

The influence of two different geometries (layouts) and two structures of high-speed photodiodes in fully standard 0.18 /spl mu/m CMOS technology on their intrinsic (physical) and electrical bandwidths is analyzed. In addition, a possible application of the integrated photodiodes for the CD and DVD optical pick-up units is discussed. Two photodiode structures with a highest responsivity are studied: nwell/p-substrate and p+/nwell/p-substrate (double photodiode). The photodiode bandwidths are compared for /spl lambda/=780 nm and /spl lambda/=650 nm wavelength, corresponding to the lasers for CD and DVD, respectively. Slow substrate current component limits the intrinsic bandwidth of nwell/p-substrate and p+/nwell/p-substrate photodiodes to 6MHz and 7MHz, for a CD application as well as 70MHz and 100MHz for a DVD application. The electrical bandwidth of these diodes in combination with typical transimpedance amplifiers, will be always larger than the calculated intrinsic bandwidths meaning that the diode capacitance is not critical in total photoreceiver design

Monolithic Integration of a Novel Microfluidic Device with Silicon Light Emitting Diode-Antifuse and Photodetector

Light emitting diode antifuse has been integrated into a microfluidic device that is realized with extended standard CMOS technological steps. The device comprises of a microchannel sandwiched between a photodiode detector and a nanometer-scale diode antifuse light emitter. Within this contribution, the device fabrication process, working principle and properties will be discussed. Change in the interference fringe of the antifuse spectra has been measured due to the filling of the channel. Preliminary applications are electroosmotic flow speed measurement, detection of absorptivity of liquids in the channe

Analysis of total dose-induced dark current in CMOS image sensors from interface state and trapped charge density measurements

The origin of total ionizing dose induced dark current in CMOS image sensors is investigated by comparing dark current measurements to interface state density and trapped charge density measurements. Two types of photodiode and several thick-oxide-FETs were manufactured using a 0.18-µm CMOS image sensor process and exposed to 10-keV X-ray from 3 krad to 1 Mrad. It is shown that the radiation induced trapped charge extends the space charge region at the oxide interface, leading to an enhancement of interface state SRH generation current. Isochronal annealing tests show that STI interface states anneal out at temperature lower than 100°C whereas about a third of the trapped charge remains after 30 min at 300°C

Analysis of the high-speed polysilicon photodetector in fully standard CMOS technology

A high-performance lateral polysilicon photodiode was designed in standard 0.18 um CMOS technology. The device has a frequency bandwidth far in the GHz range: the measured bandwidth of the poly photodiode was 6 GHz, which gure was limited by the measurement equipment. The high intrinsic (physical) bandwidth is due to a short excess carrier lifetime. The external (electrical) bandwidth is also high because of a very small parasitic capacitance (<0.1 pF). This is the best bandwidth performance among all reported diodes designed in a standard CMOS. The quantum efficiency of this poly photodiode is 0.2% due to the very small light sensitive diode volume. The diode active area is limited by a narrow depletion region and its depth by the technology

Low-frequency noise impact on CMOS image sensors

CMOS image sensors are nowadays extensively used in imaging applications even for high-end applications. This is really possible thanks to a reduction of noise obtained, among others, by Correlated Double Sampling (CDS) readout. Random Telegraph Signal (RTS) noise has thus become an issue for low light level applications especially in the context of downscaling transistor size. This paper describes the analysis of in-pixel source follower transistor RTS noise filtering by CDS circuit. The measurement of a non Gaussian distribution with a positive skew of image sensor output noise is analysed. Impact of dimensions (W and L) of the in-pixel source follower is demonstrated. Circuit to circuit pixel output noise dispersion on 12 circuits coming from 3 different wafers is also analysed and weak dispersion is seen