Si-base Ge Quantum-Dots Photodetector Used In Fiber Communication Field

The advantages of fiber communication system is huge-capacity,low-cost, broad-band and low-loss,also the Si-based semiconductor devices have the advantages of mature production technology and low production costs. How to integrate the advantages of both? Developing Si-base Ge Quantum-Dots photodetector used in fiber communication field is the right way.It will prepare for ultra-large-scale optoelectronic integrated communications and future photonic communication.After all it will benefit the mankind.Ultra-High Vacuum Chemical Vapor Deposition(UHV/CVD) System is adopted in this thesis to make a study of Ge quantum dots which is grown on the Si-based with the thermodynamic and kinetic theiry of S-K growth model.After a systematically study,We got the optimal conditions for single-layer growth of Ge quantum dots:Temperature T=550℃;time t =5min;GeH4 flow=lsccm.Then got the optimal growth conditions for multi-layer structure.Final we successfully developed multi-layer PIN structure Ge quantum dots detector material on Si-based.We adopt the traditional semiconductor technology to develop the semiconductor raw material into semiconductor devices.From material cleaning to the device package,lithography with "Ⅰ","Ⅱ" and "Ⅲ" Mask version are carried out.SiO2 insulation layer and Al electrode are deposited with dry and wet etching reformation of material surface.At lase we do the test work:Electrical performance and spectral response of the device are measured.Especialy the Photoelectric response test for the Optical Fiber Communication Band(1.33um-1.55um).From the test,we can see that:The functions of the device in line with the basic design;Devices with better characteristics of dark current(0.043mA/W -3V bias);due to lowe Ge-component materials the device show a low Responsiveness as 0.0014mA/W -4V bias in the Photoelectric response test for the Optical Fiber Communication Band(1.33um-1.55um).In the end,the author summarize the experience in the development of the Ge quantum dots optoelectronic devices,and put forward measures to improve the device performance to direct the further work.