氮掺杂氧化镓薄膜为过渡层制备氮化镓纳米线及其探测器

发布时间：2018-01-03 22:17

  本文关键词：氮掺杂氧化镓薄膜为过渡层制备氮化镓纳米线及其探测器　出处：《哈尔滨工业大学》2015年博士论文　论文类型：学位论文

  更多相关文章： 氧化镓薄膜 氮化镓纳米线 磁控溅射 化学气相沉积 紫外探测器

【摘要】：氮化镓(Ga N)纳米线,作为典型的宽禁带半导体纳米材料,不仅具有Ga N体材料优异的光电性能,还兼具了纳米材料的特性,在激光器、发光二级管、紫外探测器和场效应晶体管等纳米光电器件中具有广阔的应用前景。但是,Ga N纳米线在材料的制备上仍然存在催化剂粒子污染、制备成本高和参数复杂等问题,严重限制了Ga N纳米线的质量及其器件性能。本论文以氮掺杂氧化镓(Ga_2O_3)薄膜为过渡层来制备无催化剂粒子污染的Ga N纳米线,并利用Ga N纳米线制备出一种金属-半导体-金属(MSM)型紫外探测器。本论文的主要研究内容有:采用磁控溅射法在蓝宝石(0001)衬底上制备出高质量的氮掺杂Ga_2O_3薄膜,研究了溅射气压、氮气(N2)流量、薄膜厚度和退火气氛对氮掺杂Ga_2O_3薄膜的表面形貌、结构特性和光学性能的影响;采用化学气相沉积(CVD)法,以氮掺杂Ga_2O_3薄膜为过渡层制备无催化剂粒子污染的Ga N纳米线,研究了生长温度和氨气(NH_3)流量对Ga N纳米线的表面形貌、拉曼特性和发光性能的影响;以Ga N纳米线为光敏材料,制备出一种MSM型紫外探测器,并对其性能进行评价。磁控溅射法制备氮掺杂Ga_2O_3薄膜的试验研究表明,制备的氮掺杂Ga_2O_3薄膜表面光滑,表面粗糙度Ra均小于3nm。氮掺杂Ga_2O_3薄膜的晶体结构为单斜晶系结构。随着溅射气压、N2流量和薄膜厚度的增加,氮掺杂Ga_2O_3薄膜的结晶性能先逐渐提高后变差。氮掺杂Ga_2O_3薄膜表现出良好的光学质量,在400~800nm的可见光范围内的平均透过率大于80%。氮掺杂Ga_2O_3薄膜的光学带隙随着溅射气压的增加而变大,随着N2流量和薄膜厚度的增加而减小。在800℃的N2、氧气和空气中分别退火后,氮掺杂Ga_2O_3薄膜的结晶性能均得到了改善,可见光区的平均透过率达到85%。化学气相沉积法制备Ga N纳米线的试验研究表明,以氮掺杂Ga_2O_3薄膜为过渡层制备的Ga N纳米线为单晶的六方纤锌矿结构。随着生长温度从850℃增加到1000℃时,Ga N产物的表面形貌由一维的纳米线结构变为多面体的晶体颗粒。随着NH_3流量从160sccm逐渐降低到80sccm时,Ga N纳米线的平均直径逐渐变小。Ga N纳米线表现出拉伸应力的作用,拉伸应力的大小随着NH_3流量的降低而变小。Ga N纳米线的光致发光谱由紫外发光峰(~365nm)和黄光发光峰(~590nm)组成。以Ga N纳米线为光敏材料制备MSM型紫外探测器的试验研究表明,该紫外探测器具有2.3×10~(-6)A的暗电流和2.4×10~(-4)A的光电流,其光电流为Ga N薄膜基紫外探测器的92倍,但暗电流也同时增加。与Ga N薄膜基紫外探测器相比,Ga N纳米线基紫外探测器具有更大的光响应度和紫外/可见光抑制比,360nm附近的响应度为2.52A/W、探测率为1.17×10~(12)cm·Hz~(1/2)·W-1。Ga N纳米线基紫外探测器的量子效率远大于100%,说明该紫外探测器具有较高的光电导增益效应。此外,紫外探测器的时间响应特性重复性高和稳定性好,响应时间为22μs左右。
[Abstract]:Gan (Ga N) nanowires as a wide bandgap semiconductor nano materials typical, not only has the photoelectric properties of Ga N material is excellent, but also possesses a characteristic of nano material in laser, emitting two tubes, has the broad application prospect of UV detector and field effect transistors and nano optoelectronic devices. However, Ga N nanowires in material catalyst particle pollution still exists on the preparation, preparation of complex and high cost parameters, seriously limits the quality and performance of the device Ga N nanowires. The nitrogen doped gallium oxide (Ga_2O_3) thin films as transition layer to Ga N prepared without catalyst particle pollution nanowires and nanowires were prepared by a metal semiconductor metal (MSM) by Ga N UV detector. The main contents of this paper are: using magnetron sputtering on sapphire (0001) substrates prepared by nitrogen doped Ga_2O_ with high quality The 3 film, study the sputtering pressure, nitrogen flow rate (N2), the surface morphology of thin film thickness and annealing atmosphere on nitrogen doped Ga_2O_3 films, effects of structure characteristics and optical properties; by chemical vapor deposition (CVD) method with nitrogen doped Ga_2O_3 film as buffer layer preparation without pushing Ga N catalyst particle pollution the nanowires on the growth temperature and ammonia (NH_3) surface flow on Ga N nanowires, Raman and luminescence properties of N nanowires; with Ga as the photosensitive material, the preparation of a MSM type UV detector, and to evaluate its performance. Experimental study on nitrogen doped Ga_2O_3 thin films prepared by magnetron sputtering show that the preparation of nitrogen doped Ga_2O_3 thin films with smooth surface, crystal structure and surface roughness of Ra was less than 3nm. of nitrogen doped Ga_2O_3 films is monoclinic structure. With the increase of sputtering pressure, flow rate and thickness of N2 thin film, nitrogen doped Ga_2O_3 thin films The crystallinity increased at first then worse. Nitrogen doped Ga_2O_3 thin films exhibit good optical quality, in the visible range of 400~800nm the average optical transmittance higher than 80%. of nitrogen doped Ga_2O_3 band gap of the films increased with the sputtering pressure increases, decreases with the increase of N2 flow rate and film thickness in 800. C N2, oxygen and air respectively after annealing, the crystallization properties of nitrogen doped Ga_2O_3 thin films were improved, the visible transmittance reached 85%. study on Preparation of Ga chemical vapor phase deposition method N nanowires show that with nitrogen doped Ga_2O_3 film Ga transition layer of N nanowires prepared by six square single crystal wurtzite structure. With the growth temperature increased from 850 degrees to 1000 degrees, the surface morphology of Ga nanowires by N products into the crystal structure of one dimensional polyhedron. With NH_3 flow from the 160sccm gradually reduced to 80 sccm鏃，

本文编号：1375832