Abstract: As the integrated circuit process evolves towards 7 nm and below nodes, the wafer heating plate needs to achieve a highly uniform thermal field in vacuum environment. This article proposes an optimized arrangement method for heating elements based on the diameter/thickness ratio (K=D/δ) to address the problem of temperature uniformity caused by low thermal conductivity of stainless steel heating plates in vacuum equipment. By establishing a heat conduction radiation coupling model and combining it with finite element simulation, 120 sets of thermal field data were obtained for four typical diameters (6,8,10,12 inches) of heating plates in the thickness range of 10-30 mm. A model was established for the ratio of diameter/thickness and the optimal number of coil arrangements, and a relationship formula was fitted. The calculation results show that the residual R² of the model fitting relationship is 0.969 1. The results show that the temperature uniformity of the heating plate improves first and then deteriorates with the increase of the diameter to thickness ratio. The optimal diameter/thickness ratio is 8-12, corresponding to the optimal number of heating wire arrangement turns of 4-6. This model can provide quantitative reference for the design of stainless steel heating plates with a diameter ≤350 mm, significantly shortening the development cycle compared to traditional iterative trial and error methods.

Key words: semiconductor, stainless steel, heating plate, temperature field, diameter to thickness ratio