Control of hydrogen content in the carbon nitride materials and its development to the field emission devices based on the high-resolution laser spectroscopy

本研究旨在通过控制氢化非晶碳氮化物（a-CN_x：H）中氢原子的含量来优化其场发射性能。包含可忽略量的氢原子的氮化碳具有机械硬度的性质。另一方面，包含氢原子的那些通常是机械上柔软的：当氢原子以NH或OH基团的形式包含时，它们具有优异的电场发射特性。特别是在导电的Al掺杂ZnO单晶晶须表面包覆a-CN_x：H或a-CN_x：O：H薄膜所构成的杂化材料，有可能成为FED器件。此外，含CH_n（n=1-3）基团的a-CN_x：H材料具有储氢特性。因此，控制a-CN_x：H或a-CN_x：O：H材料中氢的量是合成具有物理性能的材料的关键技术 关于我们 本文利用微波或ECR等离子体分解氰化物（如BrCN和CH_3CN），用等离子体增强CVD法合成了氮化碳。2004年，进行了以下研究。（1）利用激光诱导荧光光谱（LIF）和静电探针法研究了微波放电Ar分解BrCN的过程以及CN自由基的形成和猝灭过程。BrCN分解的主要过程是Ar^+的电荷转移，随后是BrCN^+-e^-复合。CN自由基的主要猝灭过程是与未反应的BrCN反应。（2）根据CN自由基的激光诱导荧光光谱、流速和沉积的a-CN_x：H膜的重量确定CN自由基在a-CN_x：H膜上的粘附概率。s值在0.032-0.019的范围内，负依赖于0.3-0.7托范围内的Ar压力。这种负压依赖性的s可以解释的CN自由基的反应性的膜表面上。（3）He和BrCN混合气体的ECR等离子体化学气相沉积（ECR plasma CVD）是一种有效的合成a-CN_x：O：H的方法。少

The present study aims to optimize the electric-field-emission property of hydrogenated amorphous carbon nitrides (a-CN_x : H) by controlling the quantity of the hydrogen atoms contained. Carbon nitrides including negligible amount of hydrogen atoms have a property of mechanical hardness. On the other hand, those include hydrogen atoms are, in general, mechanically soft : they have excellent electric-field emission characteristic when the hydrogen atoms are included in the forms of the NH or OH groups. In particular, the hybridized material which consists of the electrically-conducting Al-doped ZnO single-crystal whiskers (Fig.1) coated by the a-CN_x : H or a-CN_x : O : H thin films has a possibility of the FED device. In addition, a-CN_x : H materials containing CH_n(n=1-3) groups have the hydrogen-storage characteristic. Therefore, the control of the hydrogen quantity in the a-CN_x : H or a-CN_x : O : H materials is the key technology to synthesize the materials having the physical p … More roperties hoped.In the present study, carbon nitrides are synthesized by using the plasma enhanced CVD processes by applying the decomposition of cyanides such as BrCN and CH_3CN with the microwave or ECR plasmas of rare gases. In 2004, following studies are made. (1)The decomposition process of BrCN by the microwave-discharged products of Ar and the formation and quenching processes of the precursor CN radicals were investigated based on the laser-induced fluorescence (LIF) spectroscopy and the electrostatic-probe method. The dominant process of decomposition of BrCN is the charge transfer from Ar^+ followed by the BrCN^+-e^-recombination. The dominant quenching process of CN radicals is the reaction with unreacted BrCN. (2)The sticking probability (s) of the CN radicals onto the a-CN_x : H film was determined from the LIF spectroscopy of CN radicals, flow speed, and the weight of the a-CN_x : H film deposited. The s value is in the range of 0.032-0.019 being negatively dependent on the pressure of Ar in the range of 0.3-0.7 Torr. This negative pressure dependence of s can be explained by the reactivity of the CN radicals on the film surface. (3)ECR plasma CVD of the mixed gases of He and BrCN was found to be effective for the synthesis of a-CN_x : O : H with the hydrogen amount in a controlled fashion. Less