【摘要】：量子點(diǎn)體系作為量子計(jì)算體系的一員由于其擴(kuò)展性比較強(qiáng),日益受到重視。通過(guò)自旋態(tài)的控制,半導(dǎo)體量子點(diǎn)體系有望制備成量子計(jì)算所需要的半導(dǎo)體芯片。本文以石墨烯材料為基礎(chǔ),加工制備了量子點(diǎn)器件,研究了石墨烯量子點(diǎn)的基本輸運(yùn)性質(zhì),使用CVD和機(jī)械剝離兩種石墨烯進(jìn)行了石墨烯量子點(diǎn)器件的制備,針對(duì)兩種方式的石墨烯設(shè)計(jì)了不同的實(shí)驗(yàn)方案,對(duì)量產(chǎn)量子點(diǎn)器件進(jìn)行了嘗試。通過(guò)低溫測(cè)試研究了石墨烯量子點(diǎn)的基本性質(zhì)。在量子點(diǎn)器件制備之前我們通過(guò)拉曼光譜研究了受電子束輻照后,石墨烯在空氣中的電學(xué)性質(zhì)變化,為優(yōu)化量子器件制備工藝,合理設(shè)計(jì)實(shí)驗(yàn)做了前期準(zhǔn)備。文章內(nèi)容主要有:1、通過(guò)拉曼光譜分析了石墨烯受電子束輻照后其電學(xué)性質(zhì)隨放置環(huán)境、時(shí)間的變化。實(shí)驗(yàn)中我們研究了輻照后石墨烯的電學(xué)性質(zhì)與拉曼光譜性質(zhì)。結(jié)果表明單層石墨烯易受到電子束輻照的影響。石墨烯拉曼光譜中D峰的出現(xiàn)表明電子束輻照在石墨烯晶格中引入了缺陷。石墨烯的載流子類型和電學(xué)電阻率通過(guò)電子束輻照能大范圍的改變。這說(shuō)明電子束輻照可以作為一種新的缺陷工程方法來(lái)改變石墨烯的性質(zhì)。實(shí)驗(yàn)結(jié)果對(duì)包含電子束輻照的石墨烯納米器件的制備和測(cè)量(如掃描電鏡與電子束曝光)有很重要的指導(dǎo)意義,也為優(yōu)化制備量子點(diǎn)器件實(shí)驗(yàn)步驟和工藝做了鋪墊。2、通過(guò)大量實(shí)驗(yàn)獲得了用電子束曝光制備量子點(diǎn)的工藝參數(shù),如:束流、寫場(chǎng)、調(diào)焦、劑量、臨近效應(yīng)的補(bǔ)償。實(shí)現(xiàn)了20 nm量級(jí)以下的曝光精度和高達(dá)4:1的深寬比,為精確可控制備量子點(diǎn)結(jié)構(gòu)打下基礎(chǔ)。3、基于CVD石墨烯,結(jié)合紫外光刻與電子束光刻技術(shù)制備了石墨烯量子點(diǎn)器件。實(shí)驗(yàn)使用光刻、電子束蒸鍍、氧等離子刻蝕、電子束曝光、反應(yīng)離子刻蝕、引線等工藝來(lái)完成器件的制備,獲得了成功制備量子點(diǎn)的關(guān)鍵參數(shù),如:紫外光刻曝光時(shí)間、對(duì)準(zhǔn)精度和顯影時(shí)間,電子束蒸鍍速率,氧等離子刻蝕功率,刻蝕時(shí)間,反應(yīng)離子刻蝕時(shí)間,氣體選擇比,功率,和電子束光刻調(diào)試參量等。實(shí)現(xiàn)了石墨烯量子點(diǎn)的可控制備,并對(duì)量產(chǎn)石墨烯量子點(diǎn)器件進(jìn)行了嘗試。4、基于機(jī)械剝離的石墨烯用電子束曝光方法加工制備了石墨烯量子點(diǎn)器件,篩選出了勢(shì)壘溝道電阻在25.8 k?至1000 k?的量子點(diǎn)器件,在低溫下對(duì)它們進(jìn)行了測(cè)試,實(shí)驗(yàn)測(cè)得了庫(kù)侖阻塞效應(yīng)和庫(kù)侖菱形圖,從中篩選出了合乎要求的石墨烯量子點(diǎn)器件。
[Abstract]:As a member of quantum computing system, quantum dot system is paid more and more attention because of its strong expansibility. By controlling the spin state, the semiconductor quantum dot system is expected to be used as a semiconductor chip for quantum computation. Based on graphene materials, quantum dot devices were fabricated. The basic transport properties of graphene quantum dots were studied. The graphene quantum dots were fabricated by CVD and mechanical stripping. Different experimental schemes have been designed for graphene in two ways, and quantum dot devices have been tried. The basic properties of graphene quantum dots were studied by low temperature measurement. Before the fabrication of QDs, we studied the changes of electrical properties of graphene in air by Raman spectroscopy, which was used to optimize the fabrication process of QDs and to design experiments reasonably. The main contents are as follows: 1. The electrical properties of graphene irradiated by electron beam were analyzed by Raman spectroscopy. In the experiment, we studied the electrical properties and Raman spectra of irradiated graphene. The results show that graphene monolayer is easily affected by electron beam irradiation. The appearance of D peak in graphene Raman spectra indicates that defects are introduced into graphene lattice by electron beam irradiation. The types of carriers and electrical resistivity of graphene vary widely by electron beam irradiation. This indicates that electron beam irradiation can be used as a new defect engineering method to change the properties of graphene. The experimental results are of great significance for the preparation and measurement of graphene nanodevices including electron beam irradiation, such as scanning electron microscopy and electron beam exposure. A large number of experiments have been carried out to obtain the technological parameters of the preparation of quantum dots by electron beam exposure, such as beam current, write field, focusing, dose and proximity effect compensation. The exposure accuracy of less than 20 nm and the aspect ratio of up to 4:1 are achieved. 3. Based on CVD graphene, the graphene quantum dot devices are fabricated by combining UV lithography and electron beam lithography. Photolithography, electron beam evaporation, oxygen plasma etching, electron beam exposure, reactive ion etching and lead wire were used to fabricate the device. The key parameters for the successful fabrication of quantum dots were obtained, such as the exposure time of UV lithography, Alignment accuracy and development time, electron beam evaporation rate, oxygen plasma etching power, etching time, reactive ion etching time, gas selection ratio, power, and electron beam lithography debugging parameters. The controllable preparation of graphene quantum dots has been realized, and an attempt has been made on the mass production of graphene quantum dots. 4. Graphene quantum dots were fabricated by electron beam exposure based on mechanical stripping graphene. The barrier channel resistance of 25.8 k? To 1000 k? The Coulomb blocking effect and the Coulomb rhombic diagram were measured. The graphene QDs were selected from the QDs.
【學(xué)位授予單位】：湘潭大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：O413;TN32

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 王太宏;納米器件與單電子晶體管(續(xù))[J];微納電子技術(shù);2002年02期

2 廖渝,李成貴;一種用輪廓儀測(cè)量平面度誤差的新方法[J];計(jì)量與測(cè)試技術(shù);1998年03期

相關(guān)博士學(xué)位論文 前1條

1 汪林俊;石墨烯量子點(diǎn)量子輸運(yùn)性質(zhì)的實(shí)驗(yàn)研究[D];中國(guó)科學(xué)技術(shù)大學(xué);2011年

，

本文編號(hào)：2420028