共查询到20条相似文献,搜索用时 46 毫秒
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文内报告了金刚石薄膜/立方氮化硼异质结的制备过程,然后采用自制的 测试装置对其伏-安特性进行了测试。 相似文献
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较系统地研究了不同衬底材料对制备氮化硼薄膜的影响。用热丝增强射频等离子体CVD法,以NH3,B2H6和H2为反应气体,在Si,Ni,Co和不锈钢等衬底材料上,成功生长出高质量的立方氮化硼薄膜,还用13.56MHz的射频溅射系统将c-BN薄膜沉积在Si衬底上,靶材为h-BN(纯度为99.99%),溅射气体为氩气和氮气的混合气体,所得到的氮化硼薄膜中立方相含量高于90%,用X射线衍射谱和傅里叶变换红谱对样品进行了分析表明,衬底材料与c-BN的晶格匹配情况,对于CVD生长立方氮化硼薄膜影响很大,而对溅射生长立方氮化硼薄膜影响不大。 相似文献
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文内报告了尺寸为0.3×0.3 mm2的立方氮化硼单晶的N-型掺杂,然后 用特殊的测量装置测量了N-型立方氮化硼的欧姆接触之后的伏-安特性。 相似文献
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以X射线衍射分析作参比,分析了高度三维有序到近乱层结构的9种六方氮化硼的红外和拉曼光谱,并进行了立方氮化硼的高温高压合成。光谱分析表明,随着晶性的降低,六方氮化硼的低频红外吸收峰的位置及拉曼谱线等基本振动光谱发生明显的特征性的变化,并伴随出现各自不同的次级光谱结构。合成结果表明,在触媒作用下,立方氮化硼的形成需要六方氮化硼原料有一定的结晶度,但立方氮化硼合成效果与六方氮化硼结晶度并非是简单的单调关系。对振动光谱和合成试验的结果进行了讨论。 相似文献
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Abstract FT-IR Spectroscopy have been used for identifying both the structure of BN and the intensity of the compressive stress in cubic boron nitride (c-BN) film prepared by a unbalanced of (13.56 MHz) magnetron sputtering of a hexagonal boron nitride target in a mixture argon and nitride discharge. A T(temperature) - V(negative bias) phase diagram was obtained using the phase structure identify by IR spectra. Comparing the reflection infrared spectra (RIR) with the transmission infrared spectra (TIR) measured from same c-BN film, it is firstly found that RIR peak position of c-BN is lower than TIR peak position of c-BN, this means that the compressive stress on the surface layer of c-BN film is smaller than that inside c-BN film, may be this is the reason why thicker c-BN film can not be synthesized. A higher IR peak position of 1064 cm?1 and a lower peak position 1004.7 cm?1 were detected from a broken and partly peeled off c-BN film. The peak position of 1064 cm?1 agrees with that of bulk c-BN at 1065 cm?1 which was synthesized at high temperature and high pressure, while the peak position of 1004.7 cm?1 accords well with the result calculated (1004 cm?1) by Wentzcovitch and it may be closes to that of the stress free value of c-BN. Using the result measured by Ulrich, the shift rate of IR peak position of c-BN in the films is about 3.8 cm?1/Gpa to be obtained. 相似文献
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从热力学角度计算出了以六角氮化硼为原料、用高压触媒法合成立方氮化硼时所形成稳定的临界晶粒半径rk的大小,当p=6.0 GPa、T=1 600 ℃时,rk≈15 nm。分析了rk的大小与合成温度、压力的关系,以及在给定压力下立方氮化硼晶粒转化率与温度的关系。结果表明:在立方氮化硼稳定区,在相同压力下,rk随温度的升高而增大;在相同温度下,rk随压力的升高而减小,rk越小立方氮化硼晶粒的转化率越高。计算结果与实际合成实验所得结果完全一致。 相似文献
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对于在高温、高压下合成的人工立方氮化硼(cBN)片状单晶进行了紫外吸收光谱和第一性原理的能带结构研究。实验中采用了UV WINLAB光谱分析仪,数据分析由MOLECULAR SPECTROSCOPY软件进行拟合运算,通过特殊的石英夹具对样品的测试表明cBN的紫外吸收波长限为198 nm,带隙为6.26 eV。结合第一性原理计算的cBN的能带结构和电子态密度的计算,可以证实导致紫外光吸收的过程是价带电子吸收光子到导带的间接跃迁。文章实验结果与目前报道的cBN能带结构中禁带宽度的吻合较好,表明cBN具有良好的紫外特性,是一种具有发展前景的紫外光电和高温半导体器件材料。 相似文献
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Cubic boron nitride (c-BN) films were deposited on highly-oriented (111) bulk c-BN crystal by using the rf magnetron sputtering method. The growth films are characterized by micro-Raman spectroscopy (μ-RS) and scanning electron microscopy (SEM), The results show that the high crystallization electron transparent c-BN films in thickness of about 10μm are obtained, Island and step growth models are clearly shown. 相似文献
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A unusual electrochromism is observed in amber cubic boron nitride (cBN) single crystals when breakdown possibly related to impurities and defects occurs. The electrochromism induces an abrupt increase in the absorption coefficient of the cBN crystals within the visible and infrared region. The change of the absorption coefficient of cBN crystal can be increased linearly by raising the current after the electrochromism occurs, whereas it is irrelevant to the polarization of the incident light. The absorption related to the electrochromism in the cBN single crystal has potential applications in designing and manufacturing electro-optical modulators, optical switches, and other optoelectric devices. 相似文献
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对于微小尺寸的N型宽禁带立方氮化硼(CBN)半导体晶体,在施加恒稳电场的情况下,观察到电致发光现象。通过置CBN单晶样品于光栅单色仪抛物面反射镜焦点的方法,对于CBN的蓝紫光辐射获得了测试系统的最大入射光通量和理想的信噪比。在350~450 nm波长范围内,CBN加上4.7×106 V·cm-1恒稳电场条件下,测量出立方氮化硼的蓝紫光发射光谱。同时,结合基于第一性原理的GGA方法计算出的立方氮化硼能带结构和电子态密度,以及测量得到的非线性j-E关系和电击穿特性,讨论了发光机理。提出了在雪崩击穿前的缺陷偶极子极化和击穿后,产生大量的激发态电子,电子在Γ能谷和X能谷间迁移的发光机制。 相似文献
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Cubic boron nitride single crystals are synthesized with lithium nitride as a catalyst under high pressure and high temperature. The main phases in the near-surface region, which around the single crystal are determined as a mixture of hexagonal boron nitride (hBN), cubic boron nitride (cBN) and lithium boron nitride (Li3BN2). High resolution transmission electron microscopy examinations show that there exist lots of nanometer-sized cubic boron nitride nuclei in this region. The interface phase structures of cubic boron nitride crystal and its near-surface region are investigated by means of transmission electron microscopy. The growth mechanism of cubic boron nitride crystal is analyzed briefly. It is supposed that LisBN2 impels the direct conversion of hBN to cBN as a real catalyst, and cBN is homogeneously nucleated in the molten state under high pressure and high temperature. 相似文献