本文選題：GaN + 納米結(jié)構(gòu)��； 參考：《山東師范大學(xué)》2010年碩士論文

【摘要】： 半導(dǎo)體產(chǎn)業(yè)發(fā)展經(jīng)歷了第一代半導(dǎo)體材料Si、Ge等,第二代半導(dǎo)體材料GaAs、GaP等以及第三代半導(dǎo)體材料SiC、ZnSe、GaN等。以氮化鎵(GaN)為代表第三代半導(dǎo)體材料與前兩代相比,具有高熱導(dǎo)率、耐高溫、抗輻射、化學(xué)穩(wěn)定性好、高強度和高硬度、寬直接帶系,內(nèi)、外量子效率高等特性,更適合于制作高溫、高頻及大功率電子器件及短波激光器,在微電子和光電子領(lǐng)域具有廣闊的應(yīng)用前景。由于一維GaN納米材料具有許多新奇的物理特性而作為新穎的低維材料越來越多引起了人們的研究興趣。隨著GaN基器件的發(fā)展需求,為了更好地實現(xiàn)其光電子特性,適當(dāng)?shù)膿诫s是非常有必要的。摻有Mn、Fe等過渡金屬元素的Ⅲ—Ⅴ族稀磁半導(dǎo)體(DMS)材料,由于其具備半導(dǎo)體和磁性材料的綜合特性,可望廣泛應(yīng)用于未來的磁(自旋)電子器件。摻Mn的氮化鎵基稀磁半導(dǎo)體材料的居里溫度超過室溫,是能實現(xiàn)室溫或更高溫度下載流子誘導(dǎo)鐵磁性的優(yōu)選材料。于是在實現(xiàn)GaN一維納米結(jié)構(gòu)生長的基礎(chǔ)上,進一步實現(xiàn)GaN納米結(jié)構(gòu)的Mn摻雜意義重大。 本文采用共濺法制備Mn摻雜GaN納米結(jié)構(gòu)。用X射線衍射(XRD)、掃描電子顯微鏡(SEM)、高分辨透射電鏡(HRTEM)、傅里葉紅外吸收譜(FTIR)、X射線光電子能譜(XPS)和光致發(fā)光譜(PL)等測試手段詳細分析了Mn摻雜GaN納米材料的結(jié)構(gòu)、組分、形貌和光致發(fā)光特性。研究了不同的氨化溫度、不同的氨化時間和不同氨氣流量對GaN納米結(jié)構(gòu)的影響,初步提出并探討了此方法合成GaN納米結(jié)構(gòu)的生長機制。所取得的主要研究結(jié)果如下: 1.用共濺射和氨化制備Mn摻雜GaN納米結(jié)構(gòu) 利用磁控濺射法在Si襯底上濺射Mn/Ga_2O_3層狀結(jié)構(gòu)薄膜,然后對濺射的Mn/Ga_2O_3層狀薄膜在氨氣氣氛下退火制備GaN納米結(jié)構(gòu)。通過改變退火時間、退火溫度及氨氣流量,研究其對合成的GaN納米結(jié)構(gòu)的影響。研究結(jié)果表明:不同的退火溫度、退火時間和氨氣流量對合成GaN納米結(jié)構(gòu)都有很大影響,合成的一維納米結(jié)構(gòu)為扁平條狀六方纖鋅礦結(jié)構(gòu)的單晶Mn摻雜GaN。 2.GaN納米結(jié)構(gòu)的光學(xué)特性 室溫下,用波長為325 nm光激發(fā)樣品表面,所得PL譜只包含二個主要的發(fā)光峰,分別對應(yīng)位于388 nm和409 nm處。位于409 nm的很強的發(fā)光峰,與文獻報道的GaN體材料的發(fā)光峰相比有較大的紅移。說明Mn摻雜有效的調(diào)整了GaN納米條的能帶結(jié)構(gòu),減小了禁帶寬度,改變了其在紫外光區(qū)的發(fā)光行為。388 nm處的發(fā)光峰可能是由于導(dǎo)帶或施主態(tài)到Mn受主間的躍遷引起的。 3.對GaN納米結(jié)構(gòu)生長機制的探索 高溫下氨氣逐步分解成NH_2、NH、H_2、N_2等產(chǎn)物,固態(tài)Ga_2O_3與H_2反應(yīng)生成中間產(chǎn)物氣態(tài)的Ga_2O,在襯底處與體系中氨氣發(fā)生催化反應(yīng)得到GaN晶核,這些晶核在襯底合適的能量位置生長,成為下一個晶核生長的依托點,隨著氨化過程的進行GaN晶核繼續(xù)長成GaN微晶,當(dāng)微晶的生長方向沿著相同的方向生長,就形成了單晶GaN納米線、納米線、納米顆粒。同時氨化層狀結(jié)構(gòu)的Mn/Ga_2O_3薄膜,能使得在微晶生長過程中,會有更多的Mn離子進駐GaN晶體內(nèi)部,實現(xiàn)了Mn的有效摻雜。更深刻的原因仍在進一步的研究之中。
[Abstract]:The development of semiconductor industry has experienced the first generation of semiconductor materials Si, Ge, second generation semiconductor materials GaAs, GaP, and third generation semiconductor materials SiC, ZnSe, GaN and so on. With gallium nitride (GaN) as the representative of the third generation semiconductor materials, compared with the first two generation, it has high thermal conductivity, high temperature resistance, radiation resistance, chemical stability, high strength and hardness, wide straight. The band system, internal and external quantum efficiency, is more suitable for the manufacture of high temperature, high frequency and high-power electronic devices and short wave lasers. It has a broad application prospect in the field of microelectronics and optoelectronics. Since one dimension GaN nanomaterials have many novel physical properties, more and more new low dimensional materials have been developed. With the development of GaN based devices, in order to better realize their optoelectronic properties, proper doping is necessary. The III - V diluted magnetic semiconductor (DMS) materials with transition metal elements such as Mn and Fe are expected to be widely used in future magnetic (spin) electrons because of their comprehensive properties of semiconductors and magnetic materials. The Curie temperature of the gallium nitride based dilute magnetic semiconductor doped with Mn exceeds the room temperature. It is the preferred material to induce ferromagnetism at room temperature or higher temperature downloader. Thus, on the basis of the realization of the growth of GaN one-dimensional nanostructures, the Mn doping of GaN nanostructures is further realized.
In this paper, Mn doped GaN nanostructures were prepared by CO sputtering. The structure, composition, morphology and Photoluminescence of Mn doped GaN nanomaterials were analyzed in detail by X ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Fourier infrared absorption spectroscopy (FTIR), X ray photoelectron spectroscopy (XPS) and photoluminescence (PL). The effect of different ammoniation temperature, different ammoniation time and different ammonia flow on the GaN nanostructure was studied. The growth mechanism of GaN nanostructure was preliminarily proposed and discussed. The main results obtained are as follows:
1. preparation of Mn doped GaN nanostructures by CO sputtering and ammoniation
Mn/Ga_2O_3 layered structure films were sputtered on Si substrate by magnetron sputtering, and then the GaN nanostructures were annealed in the ammonia atmosphere by the sputtering Mn/Ga_2O_3 layer. The effects of annealing time, annealing temperature and ammonia flow on the synthesized GaN nanostructures were investigated. The time of fire and the flow of ammonia have a great influence on the synthesis of GaN nanostructures. The synthesized one-dimensional nanostructure is the single crystal Mn doped GaN. with a flat strip of six square wurtzinc structure.
Optical properties of 2.GaN nanostructures
At room temperature, the sample surface was excited with a wavelength of 325 nm light, and the obtained PL spectrum contains only two main luminescence peaks, which correspond to 388 nm and 409 nm respectively. The strong luminescence peak at 409 nm has a larger red shift compared with the luminescence peak of the reported GaN body material. It shows that Mn doping effectively adjusts the band structure of GaN nanoscale strip, and reduces the band structure of GaN nanoscale strips. The forbidden band width has changed its luminescence behavior in the ultraviolet region. The luminescence peak at.388 nm may be due to the transition between the conduction band or donor state to the acceptor of Mn.
3. research on the growth mechanism of GaN nanostructures
The ammonia gas is gradually decomposed into NH_2, NH, H_2, N_2 and other products at high temperature. The solid Ga_2O_3 and H_2 react to produce the Ga_2O in the gaseous state of the intermediate product. The nucleation of the GaN crystal is obtained at the substrate with the ammonia in the system. These nuclei grow at the appropriate energy position of the substrate and become the basis for the growth of the next nucleation. With the ammoniation process, the GaN crystal is carried out. The nucleation continues to grow into GaN microcrystals. When the growth direction of microcrystals grows in the same direction, the single crystal GaN nanowires, nanowires and nanoparticles are formed. At the same time, the Mn/Ga_2O_3 film of ammoniated layered structure can make more Mn ions in the GaN crystal during the microcrystalline growth process, and the effective doping of Mn can be realized. More profound reasons are realized. Further research is still under way.
【學(xué)位授予單位】：山東師范大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2010
【分類號】：TB383.1

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相關(guān)期刊論文 前1條

1 王基慶,陳平平,李志鋒,郭旭光,H.Makino,T.Yao,陳弘,黃綺,周均銘,陸衛(wèi);基于離子注入技術(shù)的GaMnN室溫鐵磁半導(dǎo)體制備及其表征[J];中國科學(xué)G輯:物理學(xué)、力學(xué)、天文學(xué);2003年02期

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本文編號：1923798