【摘要】：在太赫茲(THz)技術(shù)成為國(guó)際研究熱點(diǎn)的同時(shí),太赫茲高速通信器件及系統(tǒng)的研究熱潮在國(guó)內(nèi)外科研機(jī)構(gòu)及高校蔓延開(kāi)來(lái)。太赫茲吸收、濾波、開(kāi)關(guān)、調(diào)制等功能器件在太赫茲應(yīng)用系統(tǒng)中的地位相當(dāng)于眼睛、耳朵在人體的地位,是不可或缺的部件。在太赫茲波調(diào)控技術(shù)方面,有電、光、熱等多種方式的調(diào)控手段,但都存在一定的弊端。例如,半導(dǎo)體異質(zhì)結(jié)的二維電子氣對(duì)THz波的調(diào)制深度較小,熱致相變特性的二氧化釩材料對(duì)溫度的依賴(lài)特性使得器件的調(diào)制速率較慢。光控半導(dǎo)體硅(Si)調(diào)制器雖然具有較大的調(diào)制幅度和寬帶特性,并且與現(xiàn)有半導(dǎo)體工藝相兼容,是實(shí)現(xiàn)太赫茲調(diào)控器件重要方式之一。然而,受制于本征Si對(duì)光的弛豫過(guò)程,使得光摻雜的Si對(duì)THz波的調(diào)制速率最高只能達(dá)到kHz量級(jí)。本文提出一種基于摻金硅的全光學(xué)太赫茲波調(diào)制器,通過(guò)深能級(jí)摻雜改善光作用本征Si(或高阻Si)的弛豫現(xiàn)象,實(shí)現(xiàn)對(duì)THz波的高速調(diào)控。在研究不同摻雜溫度和時(shí)間對(duì)Si材料的太赫茲波調(diào)制特性的影響后,得到最佳處理工藝為900℃下熱擴(kuò)散60 min。少數(shù)載流子壽命測(cè)試的結(jié)果表明,摻雜的金(Au)原子為Si中的非平衡電子—空穴對(duì)提供有效復(fù)合中心,使其少數(shù)載流子壽命降低了2個(gè)數(shù)量級(jí)。為了進(jìn)一步提高器件對(duì)THz波束的幅度利用率,采用金的微米圓點(diǎn)陣列進(jìn)行高溫?cái)U(kuò)散摻雜,在不損失THz波透射幅度的同時(shí)提高了調(diào)制器的調(diào)制速率。該器件在0.34 THz載波的動(dòng)態(tài)調(diào)制測(cè)試中達(dá)到了4.3 MHz的調(diào)制速率,其最大調(diào)制深度約21%。此外,該器件沒(méi)有頻率選擇特性,可工作在整個(gè)太赫茲頻段內(nèi),且具有極化不敏感等特性。其次,將摻金Si與超材料相結(jié)合,實(shí)現(xiàn)具有頻率選擇特性的調(diào)制器件,在設(shè)計(jì)的工作頻點(diǎn)或帶寬內(nèi),通過(guò)光控實(shí)現(xiàn)對(duì)THz波束的調(diào)制。最后,將摻金Si器件與實(shí)驗(yàn)室現(xiàn)有的激光集成,構(gòu)建光控太赫茲高速調(diào)制器,并同過(guò)100 kHz的調(diào)制速率成功將溫度信息在0.34 THz的信道內(nèi)調(diào)制、傳輸、解調(diào)與顯示。該工作驗(yàn)證了全光控調(diào)制器的可靠性,并展示了一種THz無(wú)線通信系統(tǒng)的雛形。本論文提出的基于光控?fù)浇鸸璧奶掌澱{(diào)制技術(shù),成本低、易實(shí)現(xiàn),與半導(dǎo)體工藝相兼容。既適用于動(dòng)態(tài)光與THz波耦合的場(chǎng)合,也是構(gòu)建其他高速Si基太赫茲功能器件的重要基礎(chǔ),在太赫茲通信、探測(cè)和成像等方面均具有巨大的應(yīng)用潛力和價(jià)值。
[Abstract]:While terahertz (THz) technology has become an international research hotspot, the research boom of terahertz high speed communication devices and systems has spread in domestic and foreign scientific research institutions and universities. Terahertz absorption, filtering, switching, modulation and other functional devices in the terahertz application system as the position of the eye, ear in the human body, is an indispensable component. In the aspect of terahertz wave control technology, there are many control methods, such as electricity, light, heat and so on, but they all have some disadvantages. For example, the modulation depth of THz wave in two-dimensional electron gas of semiconductor heterojunction is small, and the temperature dependence of thermo-induced phase transition vanadium oxide material makes the modulation rate of the device slower. The optically controlled semiconductor silicon (Si) modulator is one of the most important ways to realize terahertz control devices, although it has large modulation amplitude and wide band characteristics and is compatible with the existing semiconductor technology. However, due to the relaxation process of intrinsic Si to light, the modulation rate of photo-doped Si to THz wave can only reach kHz order of magnitude. An all-optical terahertz wave modulator based on au doped silicon is proposed in this paper. Deep level doping can improve the relaxation of intrinsic Si (or high resistivity Si) and realize the high speed regulation of THz wave. After studying the effect of doping temperature and time on the terahertz wave modulation characteristics of Si materials, the optimum treatment process is obtained at 900 鈩，

本文編號(hào)：2150860