Peng Lipei, Wu Shiwei, Wei Xicheng, Peng Wei, Wang Yafeng, Liu Tengshi, Li Shaobo, Meng Xiangjun, Dong Han
School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China.
PERIC Special Gas Co., Ltd, No.6, Shiji Street, Handan City, Hebei Province 056000, China.
ACS Omega. 2024 Oct 4;9(41):42549-42556. doi: 10.1021/acsomega.4c06723. eCollection 2024 Oct 15.
Conventional powder metallurgy techniques fail to meet the demands for ultrahigh purity tungsten (UHPW) and scalable component sizes required by the semiconductor industry. In this study, ultrahigh purity (99.999998 wt %) large-size tungsten parts, with an adjustable thickness and a diameter of 350 mm, were prepared via a chemical vapor deposition (CVD) method using ultrahigh purity (99.9999 wt %) tungsten hexafluoride (WF) as the precursor. The microstructure and physical properties of the resulting CVD-UHPW were evaluated and compared with those of powder metallurgy tungsten (PM-W). The results indicate that CVD-UHPW displays a columnar grain microstructure with a lower dislocation density and internal strain, whereas PM-W shows an equiaxed grain microstructure. CVD-UHPW has a density of 19.17 g/cm, closely matching the theoretical density of tungsten (19.35 g/cm) and significantly higher than PM-W's density of 18.79 g/cm. The specific heat capacities of CVD-UHPW, measured from 298 to 1473 K, range from 0.113 to 0.146 J/g·K, similar to PM-W's range of 0.120 to 0.151 J/g·K. CVD-UHPW shows improved electrical and thermal conductivities compared to PM-W, with values ranging from 1.68 × 10 to 1.78 × 10 S/m and 105.7 to 196.4 W/(m·K) from 298 to 1473 K. This study highlights the potential of the CVD method for the large-scale production of ultrahigh purity tungsten parts, emphasizing its significant applicability across various industries.
传统粉末冶金技术无法满足半导体行业对超高纯钨（UHPW）和可扩展部件尺寸的需求。在本研究中，通过化学气相沉积（CVD）方法，以超高纯（99.9999 wt%）六氟化钨（WF）作为前驱体，制备了厚度可调、直径为350 mm的超高纯（99.999998 wt%）大尺寸钨部件。对所得CVD-UHPW的微观结构和物理性能进行了评估，并与粉末冶金钨（PM-W）的进行了比较。结果表明，CVD-UHPW呈现柱状晶粒微观结构，位错密度和内部应变较低，而PM-W呈现等轴晶粒微观结构。CVD-UHPW的密度为19.17 g/cm，与钨的理论密度（19.35 g/cm）紧密匹配，且显著高于PM-W的密度18.79 g/cm。在298至1473 K范围内测量的CVD-UHPW的比热容为0.113至0.146 J/g·K，与PM-W的0.120至0.151 J/g·K范围相似。与PM-W相比，CVD-UHPW的电导率和热导率有所提高，在298至1473 K范围内的值分别为1.68×10至1.78×10 S/m和105.7至196.4 W/(m·K)。本研究突出了CVD方法在大规模生产超高纯钨部件方面的潜力，强调了其在各个行业的显著适用性。
