CN107699863A - 一种MPCVD制备GaN纳米线的方法 - Google Patents

一种MPCVD制备GaN纳米线的方法 Download PDF

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CN107699863A
CN107699863A CN201710844514.9A CN201710844514A CN107699863A CN 107699863 A CN107699863 A CN 107699863A CN 201710844514 A CN201710844514 A CN 201710844514A CN 107699863 A CN107699863 A CN 107699863A
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王如志
姬宇航
李�瑞
严辉
张铭
王波
宋雪梅
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Abstract

一种MPCVD制备GaN纳米线的方法属于无机化合物半导体材料制备与生长方法领域。高质量GaN纳米线的可控制备是当前的一个技术难点,本发明采用设计的石英坩埚和石英罩克服了这一难点,首次采用MPCVD制备了高质量的GaN纳米线,并且摒弃了对环境有污染的NH3和危险气体H2,在整个制备过程中N2作为唯一气体,为GaN的环保绿色制备得到了一个新的突破。

Description

一种MPCVD制备GaN纳米线的方法
技术领域
本发明为微波等离子体化学气相沉积(MPCVD)绿色环保制备氮化镓(GaN)纳米线,属于无机化合物半导体材料制备与生长方法领域。
背景技术
GaN与碳化硅(SiC)、金刚石等宽带隙化合物半导体材料,是继第一代Ge、Si元素半导体、第二代砷化镓(GaAs)、磷化铟(InP)化合物半导体之后的第三代半导体材料。GaN作为一种第三代宽禁带直接带隙半导体材料,室温下禁带宽度达3.39eV,同时具有较大的电子迁移率、良好的导电导热性、高的击穿场强、较好的抗辐射性和耐高温及抗化学腐蚀性等诸多特性,已成为高能、高温及对工作环境要求较高电子元器件的优选材料。GaN基宽禁带半导体材料由于其在短波长发光二极管和激光二极管上的应用已成为研究最广泛的半导体材料之一。
目前,制备GaN纳米线有很多方法,但都具有一定的局限性,比如采用CVD制备的GaN纳米线质量较差,杂质较多,采用金属有机化合物化学气相淀积(MOCVD)制备的GaN纳米线原料较贵,且对环境和设备存在一定程度的腐蚀和污染,同时制备出的GaN纳米线大多方向性极差,这严重制约了其性能的提高。如何找到一种环保绿色同时得到高质量GaN纳米线的制备方法已成为解决GaN纳米线能否应用于纳电子器件关键,也是该领域科研工作者不懈追求的目标。微波等离子体化学气相沉积(MPCVD)由于其气密性较高,等离子体浓度大,可以摒弃对环境有污染的NH3和具有危险性的H2作为原料,快速制备高质量的GaN纳米线,但由于其特殊的腔体结构,GaN纳米线的制备还是一个难点。而我们采用特殊设计的石英坩埚克服了这一难点,首次采用MPCVD制备了高质量的GaN纳米线,并且摒弃了对环境有污染的NH3和危险气体H2,在整个制备过程中N2作为唯一气体,为GaN的环保绿色制备得到了一个新的突破。
发明内容
本发明的目的是提供MPCVD无氢法制备氮化镓纳米线。即在微波等离子体化学气相沉积系统中,以混有炭粉的Ga2O3粉末为镓源,以离子态氮为氮源,以镀有催化剂(Au)的硅片为衬底,在特殊设计的石英坩埚中通过直接反应生成氮化镓纳米线。本发明摒弃对环境和设备存在污染和腐蚀的NH3和具有较高危险的H2,采用简单易操作的实验设备和价格低廉且易获得的原料制备高质量氮化镓纳米线。通过设计的方形石英坩埚和石英罩的结合,可以使加热台的热量传导到衬底,又可以加热原料,达到了衬底和原料同时加热的目的;另外可以有效的促进反应的发生,促使向上流动的Ga蒸气与向下流动的N等离子体在石英钟罩内发生对流,让本不可能在MPCVD中发生的反应可以持续进行(如图6所示)。根据反应设备的限制,方形石英坩埚边长为30mm,高10mm,中央突出衬底插槽高10mm,宽10mm,厚度1mm;石英罩底部圆形直径为60mm,顶部镂空圆直径为20mm,顶部镂空圆中心到底部圆心距离为40mm。反应过程中通过等离子体直接在衬底周围发生的作用,增强了镓的还原,提高了反应速率,并且摒弃了在所有等离子体增强中都会用到的还原气体H2,首次采用MPCVD得到GaN纳米线。
一种MPCVD无氢法制备氮化镓纳米线的方法,其特征在于,包括以下步骤:
(1)Ga2O3粉末与炭粉以摩尔比为1:6-1:12进行混合,研磨30min得到前驱物粉体;
(2)使用镀膜仪,在经过清洗后烘干的硅衬底上镀厚度15nm的金属催化剂薄膜;
(3)将采用上述步骤制备的前驱物粉体和衬底放入设计的坩埚,再将坩埚放入微波等离子体沉积系统中的反应腔内:反应气压3torr~10torr;衬底温度800℃-900℃;N2流速5厘米3/分钟-20厘米3/分钟;微波功率300W-500W,调节微波匹配器至得到亮橙色辉光的等离子气体;反应时间10分钟以上;
设计的坩埚包含方形石英坩埚和上部开口的半球面型石英罩。
具体反应时间视所需要制备纳米线长度(时间与长度成正比)而定。
进一步,石英罩底部圆形直径为60mm,顶部开口对应的圆直径为20mm,顶部开口对应的中心到底部圆心距离为40mm。
进一步方形石英坩埚边长为30mm,高10mm,中央突出衬底插槽(可镂空)高10mm,宽10mm,厚度1mm。
对制得的氮化镓纳米线的结晶性、微结构、形貌、光学性能进行分析和对比。采用X射线衍射仪分析氮化镓的物相;通过扫描电子显微镜和透射电子显微镜分析氮化镓的形貌和结晶性;使用拉曼测试系统分析实验条件对氮化镓形貌和性能产生的影响。光学性能以荧光光谱仪进行测试。
本发明具有以下优点和效益:
(1)在设计的方形石英坩埚和石英罩中通过直接反应生成氮化镓纳米线。本发明摒弃对环境和设备存在污染和腐蚀的NH3和具有较高危险的H2,采用简单易操作的实验设备和价格低廉且易获得的原料制备高质量氮化镓纳米线。通过设计的方形石英坩埚和石英罩的结合,可以使加热台的热量传导到衬底,又可以加热原料,达到了衬底和原料同时加热的目的;另外可以有效的促进反应的发生,促使向上流动的Ga蒸气与向下流动的N等离子体在石英钟罩内发生对流,让本不可能在MPCVD中发生的反应可以持续进行(如图6所示),且反应过程中通过等离子体直接在衬底周围发生的作用,增强了镓的还原,提高了反应速率,并且摒弃了在所有等离子体增强中都会用到的还原气体H2,即N2作为通入的唯一气体,首次采用MPCVD得到GaN纳米线。
(2)制备的氮化镓纳米线具有典型的纳米线光致发光特征。
附图说明
图1为本发明装置整体示意图以及设计的石英坩埚和石英罩示意图和三视图,其中
1.石英罩
2.衬底
3.方形坩埚
4.加热平台
5.石英窗口
6.微波通道
图2为实施例1制备的氮化镓纳米线的SEM图谱
图3为实施例1制备的氮化镓纳米线的XRD图谱
图4为实施例1制备的氮化镓纳米线的Raman图谱
图5为实施例1制备的氮化镓纳米线的PL图谱
图6为反应原理图
具体实施方式:
下面通过实施例对本发明近行进一步说明,本发明绝非局限于所陈述的实施例。
实施例1
(1)Ga2O3粉末与炭粉以摩尔比1:6的比例进行混合,研磨30min得到前驱物粉体;
(2)将经过清洗后烘干的硅片使用SBC-12小型离子溅射仪镀Au10s,得到表面有15nm左右金膜的衬底;
(3)将采用上述方法制备的混合粉末和衬底,放入设计的石英坩埚和石英罩中,采用微波等离子体化学气相沉积法:在反应气压3torr,衬底温度880℃,N2流速10厘米3/分钟,调节微波匹配电源功率至300W得到亮橙色辉光,反应时间30min条件下得到氮化镓纳米线。其SEM图谱见图2,XRD图谱见图3,Raman图谱见图4,PL图谱见图5,反应原理图见图6。
实施例2
(1)Ga2O3粉末与炭粉以摩尔比1:12的比例进行混合,研磨30min得到前驱物粉体;
(2)将经过清洗后烘干的硅片使用SBC-12小型离子溅射仪镀Au10s,得到表面有15nm左右金膜的衬底;
(3)将采用上述方法制备的混合粉末和衬底,放入设计的石英坩埚和石英罩中,采用微波等离子体化学气相沉积法:在反应气压10torr,衬底温度850℃,N2流速20厘米3/分钟,调节微波匹配电源功率至500W得到亮橙色辉光,反应时间30min条件下得到氮化镓纳米线。
其SEM图谱,XRD图谱,Raman图谱,PL图谱,反应原理图和实施例1的基本上没有区别,就不再赘述。

Claims (3)

1.一种MPCVD制备GaN纳米线的方法,其特征在于,包括以下步骤:
(1)Ga2O3粉末与炭粉以摩尔比为1:6-1:12进行混合,研磨30min得到前驱物粉体;
(2)使用镀膜仪,在经过清洗后烘干的硅衬底上镀厚度15nm的金属催化剂薄膜;
(3)将采用上述步骤制备的前驱物粉体和衬底放入设计的坩埚,再将坩埚放入微波等离子体沉积系统中的反应腔内:反应气压3torr~10torr;衬底温度800℃-900℃;N2流速5厘米3/分钟-20厘米3/分钟;微波功率300W-500W,调节微波匹配器至得到亮橙色辉光的等离子气体;反应时间10分钟以上;
设计的坩埚包含方形石英坩埚和上部开口的半球面型石英罩。
2.根据权利要求1所述的方法,其特征在于:石英罩底部圆形直径为60mm,顶部开口对应的圆直径为20mm,顶部开口对应的中心到底部圆心距离为40mm。
3.根据权利要求1所述的方法,其特征在于:方形石英坩埚边长为30mm,高10mm,中央突出衬底插槽高10mm,宽10mm,厚度1mm。
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CN102936006A (zh) * 2012-10-24 2013-02-20 北京工业大学 一种低成本低污染的氮化镓纳米线的制备生成方法
CN103173738A (zh) * 2013-03-22 2013-06-26 新疆大学 一种Ga空位可调的GaN纳米结构的制备方法
CN103774230A (zh) * 2014-01-25 2014-05-07 北京工业大学 一种无氨化制备氮化镓纳米线的方法
CN105040096A (zh) * 2015-06-25 2015-11-11 广东工业大学 一种新型螺旋状GaN单晶纳米线及其制备方法

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CN111206236A (zh) * 2020-01-10 2020-05-29 北京工业大学 一种Mg掺杂GaN纳米线结构的制备方法
CN111206236B (zh) * 2020-01-10 2022-03-15 北京工业大学 一种Mg掺杂GaN纳米线结构的制备方法

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