The Study On Optical Detection Material And Device Based On Carbon Nanotube

The rapid development of information industry has higher and higher demand ofcircuit integration,and nano quantum devices were generated,as a kind of nano material.Carbon nanotubes have unique mechanical and electrical properties,and received a lot ofpublicity.Now,the application research of carbon nanotubes is still in its early stage,and thework in the past was focused on its growth and characterization.In this paper,a CNTsisomeric homojunction photodiode is proposed and simulated;then CNTs film opticaldetector was produced,and its electrical property and noise characteristic are investigated.This paper simulates the process that carriers are accelerated under the internalelectric field of CNTs p-n junction photodiode with a classical Langevin equation,andfurther discusses the physical mechanism for efficient carrier multiplication in CNTs p-njunction photodiode.It has been found that the carrier multiplication rate has certaindependence on the depletion length and ambient temperatureinternal electric field intensityin p-n junction. We propose CNTs isomeric homojunction photodiode,in order to realizeefficient carrier multiplication at room temperature. Theoretical calculation indicate thatcarrier avalanche multiplication will happen in CNTs isomeric homojunction at roomtemperature and zero bias condition,and this kind of CNTs p-n junction is more practicalthan homojunction.Metal electrodes are fabricated via lithography techniques on the carbon nanotubefilms.The optical response properties of CNT film are analyzed. Since the collisionexcitation of carriers is strongly dependent on the temperature, the temperaturedependence of the carbon nanotube films characteristics was investigated by means ofexperiment.The CNT optical detector noise characteristic is analyzed through noise testsystem.And finally integrate the experiment and theory,the prospect of CNT in infrareddetection is analyzed.