纳米金属—半导体结构中新型光电效应研究

发布时间：2018-04-18 07:24

本文选题：侧向光伏效应 + 光致极性电阻效应　；参考：《上海交通大学》2015年博士论文

【摘要】：纳米金属半导体材料由于其特有的功能性和众多新奇的物理效应,在能源、航空、生物、信息等高科技领域产生深远影响和广阔应用前景。近十多年来的大量报道都表明,比之块体材料,纳米尺度的材料拥有更加突出的光电性能,相关的制备手段以及效应研究一直是当今科研的前沿课题。本论文是针对这一前沿课题的探索性研究,目的是通过对于纳米材料的光伏效应、光致极性电阻效应以及光调控开关效应的研究,发现新的光电现象,探索和揭示新的物理机理,并最终获得具有实用价值的、外场(光场)调控的纳米光电材料以及光电传感设备。论文中所研究的材料属于纳米金属氧化物半导体结构,涵盖了超薄纳米薄膜、量子点体系和胶体晶体体系。通过在多种金属氧化物半导体纳米结构上进行侧向光伏效应测量,获得如下实验结果:在Ti/Ti O2/Si纳米薄膜上获得了当前报导中的最大侧向光伏灵敏度169 m V/mm,对比其它研究组的报道(~20m V/mm)有着显著提升;对比Cr/Si O2/Si纳米薄膜在暗场条件下的电导性能与灵敏度,完善了侧向光伏效应光电子扩散模型机制;首次在Zn/Cd Se量子点/Si结构上发现了具有量子点增强特性的侧向光伏效应,扩展了量子点在光电器件方面的应用;首次在Au/Si O2胶体晶体/Si结构上发现侧向光伏效应,所获得的灵敏度(86m V/mm)比同组份材料的薄膜结构的近5倍。本论文中还有另一个研究方向——纳米材料电阻的光响应。我们在Zn/Cd Se量子点/Si结构上拓展了光致极性电阻效应:其电阻变化率高达280%,而无量子点嵌套的结构仅有15%。在Au/Si O2胶体晶体/Si结构上发现了光调控开关效应:无光情况下,材料电阻并不随扫描电压变化,而有激光照射时,电压的变化可以控制材料电阻高、低电阻态之间的转换,这是外加电场和光场共同作用的一个新现象。
[Abstract]:Nanometallic semiconductor materials have profound influence and broad application prospect in the fields of energy aviation biology information and so on because of their unique functions and many novel physical effects.A large number of reports over the past decade have shown that nanoscale materials have more outstanding optoelectronic properties than bulk materials, and related preparation methods and effects have been the frontier of current scientific research.The purpose of this thesis is to find new photovoltaic phenomena through the study of photovoltaic effect, photoinduced polarity resistance effect and optically regulated switching effect of nanomaterials.To explore and reveal the new physical mechanism, and finally to obtain practical, external field (light field) controlled nano-optoelectronic materials and photoelectric sensing equipment.The materials studied in this paper are nanometallic oxide semiconductors, including ultrathin nanocrystalline films, quantum dot system and colloidal crystal system.By measuring the lateral photovoltaic effect on various metal oxide semiconductor nanostructures,The experimental results are as follows: the maximum lateral photovoltaic sensitivity of 169mV / mm has been obtained on the Ti/Ti O2/Si nanocrystalline thin films, which is significantly improved compared with that reported by other research groups (20 MV / mm).The photoelectron diffusion mechanism of lateral photovoltaic effect was improved by comparing the conductivity and sensitivity of Cr/Si O2/Si nanocrystalline films under dark field conditions, and the lateral photovoltaic effect with enhanced quantum dot properties was first found on Zn/Cd se quantum dots / Si structure.The application of quantum dots in optoelectronic devices is extended, and the lateral photovoltaic effect is first found on the Au/Si O2 colloidal crystal / Si structure. The sensitivity obtained is nearly 5 times higher than that of the thin film structure of the same composition material.Another research direction in this thesis is the photoresponse of nano-material resistance.We extend the photoinduced polarity resistance effect in the Zn/Cd se quantum dots / Si structure: the resistance change rate is as high as 280, while the structure without quantum dot nesting is only 15.In the structure of Au/Si O 2 colloidal crystal / Si, the photo-controlled switching effect is found: in the absence of light, the material resistance does not change with the scanning voltage, but with laser irradiation, the change of the voltage can control the transition between the high and low resistance states of the material.This is a new phenomenon of the interaction of external electric field and light field.
【学位授予单位】：上海交通大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TB383.1

【相似文献】