Research On Several Key Issues High-Speed Optoelectronic Devices Integration Structure And Process Compatibility

The optical fiber communication system is gradual developing toward the next-generation optical network with integration, intelligent, low-cost and high reliability features. Optoelectronic devices and electronic devices imply higher requirements in the communication system. This indicates that highly functional and optoelectronic integration device technology, which provides a small size, low cost and stable performance will be important to support next-generation optical communication system. Because the receiver end is an important key component to build an optical fiber communication system, it is extremely significant in developing related research on the receiver end of optoelectronic integration devices. The silicon-based electronic devices which are mature technology, low cost and high stability features had been widely used. The III-V semiconductors of active optical devices are the key component in fiber optic communication systems. Problems with integration structure, interconnection and packaging technology, process compatibility are some of the problems being faced to take each advantage of this two types devices. Hence, research on optoelectronic integration structure and process compatibility of receiving end in optical fiber communication system is becoming a hot topic in development of high speed optoelectronic integration device.In this dissertation, optoelectronic integration device structure and process compatibility were studied. The research on optoelectronic integration devices of receiving end in optical fiber communication system was carried out. The main contents and innovations are listed as follows:1. The long wave photodetector based on InP and a receiver front end which consists of the planar photodetector and a CMOS process integration circuit was designed. The internal mechanism, frequency response, quantum efficiency of the vertical illuminated planar photodetector was studied. The influence of packaging parameter on frequency response was analysed. The key issues of metal bonding process and integration compatibility of integration receiver front-end were discussed. The responsivity of vertical illuminated planar photodetector is0.95A/W at1550nm,3-dB bandwidth is8.5GHz. The dark current is less than0.1nA, and the capacity is about0.42pF at a reverse bias of5V.3-dB bandwidth of the integration receiver front-end is about1.7GHz. The signal transmission rate of the receiver front-end is up to3Gbps.2. Furthermore, a multi-channel array optoelectronic integration receiving component was fabricated. The receiving component package technology and compatible process technology was studied. The influence of butterfly package parasitic parameter on signal transmission of optoelectronic integration receiving component was analyzed theoretically. At1550nm,3-dB bandwidth of each channel was improved to5.33GHz and4.36GHz, respectively. The improved solution of driver circuits, package interface and evaluation board was proposed. The each channel signal transmission rate exceeding10Gbps was predicted to be realized.3. Zero bias PIN photodetector based on band gradient and doping gradient profile was proposed and fabricated. The device has a maximum bandwidth efficiency product when the thickness of the absorption layer is350nm. At the1550nm and reverse bias of3.3V, the quantum efficiency is21.14%and the responsivity is0.2638A/W.3-dB bandwidth is12.27GHz at zero bias,3-dB bandwidth is14.9GHz at the reverse bias of3.3V. Zero-bias bandwidth is numerically about eighty percent of the maximum bandwidth, so it is appropriate for low power consumption optical fiber communication system.4. Signal transmission performance of Pt-Ti-Pt-Au alloy electrode was studied and optimized focusing on signal transmission coefficient and impedance. The optimum solution of signal transmission coefficient and impedance of alloy electrode was realized at the specific thickness. Overall, it decreased the RC delay effect. It focusses on resolving the problem which the frequency response of photodetector fall down seriously from10MHz to200MHz. The improved structure and process were proposed, the etching method was improved, the opening time was accurately controlled and the electrode deposition process was simplified. Simultaneously, frequency response bandwidth of photodetector was improved effectively by applying the new process technology.5. A compatibility process based on InP/Si dual-matrix composite substrate which is appropriate for high-speed optoelectronic integration devices was studied. Industrial clean and bonding process which were used to fabricate the InP/Si dual-matrix composite substrate was introduced. Wafer bonding technology was analyzed theoretically in detail. Hence, A4inch InP/Si dual-matrix composite substrate was fabricated for high-speed optoelectronic integration device. The InP/Si dual matrix composite substrate was analyzed by using scanning electron microscopy (SEM) and X-ray diffraction. The effect of this optoelectronic integration process on the wafer substrate surface was discussed. The feasibility of regrow photonics devices on industrial fabrication lines was analyzed and investigated.