Control of generation, growth, and behavior of particles in ablation plasma plume by electrmagnie field

脉冲Nd：YAG激光沉积（PLD）技术具有系统设置简单、沉积条件宽、可使用多种材料、瞬时沉积速率高等优点，近年来已成为一种广泛应用的薄膜沉积技术，但也指出了PLD技术存在的一些问题。由于该系统的沉积面积取决于等离子体羽流的大小，因此无法制备大面积薄膜。通过该系统沉积的膜的厚度是不均匀的，因为羽流中的等离子体密度的三维轮廓是不均匀的。许多微米大小的液滴叠加在通过该方法沉积的膜的表面上。这种现象几乎总是在用这种方法生长的薄膜上观察到。从膜质量的观点来看，这些微米尺寸的液滴的存在是PLD工艺的主要缺点。为了解决这些问题， 关于我们 为了获得大面积无液滴的均匀薄膜，发展了一种新的横向磁场PLD方法。本文研究了横向磁场对PLD法制备大面积无液滴均匀薄膜的影响，利用ICCD相机测量了等离子体羽流的二维发射轮廓，改变了等离子体羽流在横向磁场中的形状。与非横向磁场相比，横向磁场中基板上的液滴密度降低。这些实验结果表明，利用正交磁场可以制备出高质量、大面积的均匀薄膜，而且由于这种多功能性，我们已经利用正交磁场PLD方法制备出了碳化钨、碳化硅、碳化铬、立方氮化硼、氮化碳、氮化硅等多种功能薄膜。与无磁场条件下相比，所有这些薄膜的质量都有所提高。少

Pulsed Nd : YAG laser deposition (PLD) method has become a widely used technique for the deposition of thin films in the past few years due to the advantages of simple system setup, a wide range of deposition conditions, the possibility of using many kinds of materials, and a high instantaneous deposition rate.On the other hand, several problems with the PLD method have been pointed out. Because the deposition area of this system is determined by the size of the plasma plume, large-area thin films cannot be prepared. The thickness of the film deposited by this system is not uniform because the three-dimensional profile of the plasma density in the plume is not uniform. Many micron-sized droplets are superimposed on the surface of films deposited by this method. This phenomenon is almost always observed on films grown by this method. The presence of these micron-sized droplets is the main drawback of the PLD process from the viewpoint of film quality. To solve these problems and prepare … More large-area uniform thin film without droplets, a new PLD method with a cross-magnetic field has been developed. In this paper, we report the effects of the cross-magnetic field on preparing large-area uniform film without droplets by the PLD method.Two-dimensional emission profiles of the plasma plume were detected with an ICCD camera, and the shape of the plasma plume in the cross-magnetic field was changed. The density of the droplets on the substrate in the cross-magnetic field decreased in comparison with that in a non-cross-magnetic field. These experimental results suggest that high-quality and large-area uniform thin film can be prepared by using a cross-magnetic field.In addition, because of this versatility, we have developed several kinds of functional thin films such as tungsten carbide, silicon carbide, chromium carbide, cubic boron nitride, carbon nitride, and silicon nitride by using the PLD method with cross-magnetic field. All of these films' quality increase, as compared with non-magnetic field. Less