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? ? ? ?In the semiconductor industry, tungsten thin films are mainly used as materials constituting electronic parts such as gate electrodes or wiring materials. The requirements for integration, reliability, functional characteristics and processing speed of these electronic components are increasing day by day. Tungsten has the characteristics of low resistance and high heat resistance, and is widely used in these electronic components, and well meets the above requirements. Tungsten thin films can be prepared by physical vapor deposition (PVD) technology, which is obtained by sputtering a high-density, high-purity tungsten target.