150mm NN+结构的外延材料厚度与电阻率分布控制工艺研究

Study on Control Technology of Thickness Distribution and Resistivity Distribution of Epitaxial Material of 150mm Size N/N+ Structure

阐述利用150mm直径的重掺杂硅抛光片,外延生长N/N+结构的厚层高阻外延层,通过流场结构以及热场结构的设计与实施,并与外延层厚度、电阻率均匀性的交互作用规律相结合,通过傅立叶变换红外线光谱分析仪(FT-IR)、电容-电压测试仪(C-V)等测试设备对外延厚度和电阻率参数进行了分析,得到了一种不均匀性<2%的外延层。结果显示,随着两边的气流的增大,外延层的参考平边厚度也随之增大,而平均厚度则降低了。随着径向温度偏差的降低,外延层的电阻率与厚度不均匀性有显著的提高。采用这种趋势特点,通过对气流场和热场结构的制备,得到了外延层的电阻率和厚度不均匀性的显著改善。

This paper describes that a 150mm diameter heavily doped silicon polished wafer is used as the reaction substrate to epitaxially grow a thick high-resistance epitaxial layer of N/N+ structure. The interaction law of layer thickness and resistivity uniformity was studied in detail, and the epitaxial electrical parameters were analyzed in combination with Fourier Transform Infrared Spectroscopy(FT-IR), Capacitance-Voltage Tester(C-V) and other test equipment. Epitaxial layers with <2% inhomogeneity have been successfully fabricated. The study shows that the thickness of the flat edge of the epitaxial layer of the epitaxial wafer increases with the increase of the airflow on both sides, but the average thickness decreases with the increase of the airflow on both sides. The resistivity non-uniformity of the epitaxial layer shows a trend of obvious improvement with the decrease of the radial temperature deviation. According to this trend, the resistivity and thickness non-uniformity of the epitaxial layer prepared by debugging the flow field and thermal field structure can be lower than the high uniform level of 2%, which meets the design requirements.