一、前言从50年代中期以后,钽逐渐成为电子元件的重要材料之一。那时,因为钽的抗蚀性强、易于阳极氧化、以及其氧化膜具有优良的介电性能,所以首先用来制造钽电容器。由于在块状形式下,钽的电阻率很小(ρ=13μΩ·cm),而电阻的温度系数(TCR)又很大,所以不适于作为电阻材料。然而,在薄膜形式下,出现了钽晶的四方结构(常 I. Introduction Since the mid-1950s, tantalum has gradually become one of the important materials for electronic components. At that time, tantalum was first used for the manufacture of tantalum capacitors because of its high corrosion resistance, its ease of anodization and its oxide film’s excellent dielectric properties. Tantalum is not suitable as a resistive material because of its small resistivity (ρ = 13μΩ · cm) and large temperature coefficient of resistance (TCR) in bulk form. However, in thin film form, the tetragonal structure of tantalum appears