【作者】 宫建红；

【导师】 李木森；

【作者基本信息】 山东大学 ， 材料学， 2006， 博士

【摘要】 含硼金刚石(即Ⅱb型金刚石)是一类特殊的金刚石，在抗氧化性、耐热性和化学惰性方面都优于普通金刚石。尤其是电学性能方面，含硼金刚石具有优良的半导体性能，可以在更高温度和恶劣环境下正常工作，是一种有发展前途的高温、大功率半导体材料。随着现代化工业的飞速发展，含硼金刚石在各个行业都显示出巨大的应用前景，因此受到金刚石生产者和使用者的广泛关注。我国虽然已进入人造金刚石大国之列，但是国内的金刚石主要以中、低档次的磨料级产品为主，与国际上处于垄断地位的美国G．E．公司、南非DeBeers公司和德国Winter公司等企业的先进技术水平相比还有很大差距。因此，研究开发新型的优质金刚石单晶具有重要的现实意义。 本文以粉末冶金铁基金刚石催化剂为基础，以硼铁粉作为供硼剂，制备了用于合成含硼金刚石单晶的新型铁基含硼片状催化剂，以石墨为碳源，在高温高压条件下合成了两种含硼量不同的金刚石单晶。利用金刚石形貌测量系统(Diashape)、扫描电镜(SEM)、原子力显微镜(AFM)、透射电镜(TEM)、拉曼光谱(Raman)，红外光谱(IR)、X射线衍射仪(XRD)和场发射扫描电子显微镜(FESEM)等表征方法，对普通金刚石、含硼金刚石及含硼金刚石表面金属包膜的表面形貌和结构进行了系统的检测和分析；用静压强度仪、冲击韧性测量仪、差热分析仪(DSC)和自制的电阻—温度测量系统对含硼金刚石和普通金刚石的性能参数进行了比较和分析，结合余氏理论和程氏理论对金刚石与碳化物的电子结构和界面电子密度进行了计算分析，并用计算的结果结合相关的实验数据探讨了金刚石的形核与长大方式。 含硼金刚石的颜色因触媒中硼含量的不同而呈灰黑色或不透明的黑色，触媒中硼含量越高金刚石颜色越深，晶形主要以八面体居多。EPMA研究表明，金刚石表面硼元素的浓度随着触媒中硼含量的增加而增加：研究还表明同一类型金刚石的(111)晶面上硼元素浓度高于(100)晶面。XRD的实验结果表明金刚石中硼浓度越高，(111)晶面越发达。更多还原

【Abstract】 The boron-doped diamond, so-called Ⅱb type diamond, processes many wonderful properties such as oxidation-resistance, impact-resistance, stable chemical character and excellent semiconductor performance. So it shows exciting application in many industry fields, and especially in the electronic field. Although a large number of diamond single crystals are produced every year, the homemade diamond is mainly low-valent and the quality can not compare with that of diamond produced by several monopolized companies, such as G.E., DeBeers and Winter. Therefore it is of great significance to synthesize and investigate the excellent boron-doped diamond single crystal.In the present paper, boron-undoped diamond and boron-doped diamonds were synthesized by using different boron-doped Fe-based alloy catalysts with different composition produced by powder metallurgy. The morphology and structure of the undoped diamond, boron-doped diamond and metallic film surrounding diamond were studied by means of diamond shape measurement system (Diashape), Scanning electron microscope (SEM), Atom force microscope (AFM), Transmission electron microscope (TEM), Raman spectrum (Raman), Infrared ray (IR), X-ray diffraction (XRD) and Field emission scanning electron microscopy (FESEM). Meanwhile the character performances of the two kinds of diamonds were measured by static strength measurement, (thermal) impact toughness measurement, different thermal analysis (DTA) and homemade resistance-temperature measurement system. The nucleation and growth mechanism of the diamond were discussed according to the experimental results and carbide-diamond interface electron structures calculated via Empirical Electron theory (EET) and Thomas-Fermi-Dirac-Cheng (TFDC).The boron-doped diamonds are gray or even opaque black dependent on the boron concentration in diamond and their crystal shape is mainly更多还原