The Finite Element Analysis Of Electromagnetic Field For IC Manufacturing Equipment

Integrated circuit manufacturing technology is the essential part of the microelectronics industry, and it is important to improve the efficiency and the quality of the production at the same time. The design of the IC equipment is particularly significant, because the machining process of the microelectronics technology is mostly conducted by automatic machine. In this paper, considering the requirement of the design of IC equipment, the electromagnetic field distribution and characteristics are analyzed by the use of finite element method. The IC equipment studied in this paper is PECVD. Its technical principle is the gas contained the film atom is ionized by the microwave or the RF excitation, thus forming a plasma. Then, because of the chemical activity of the plasma, the desired film can be deposited on substrate by the reaction between matrix and plasma in the low temperature. Some process indicators, such as the uniformity of the deposited thin film, are directly affected by the distribution and movement characteristics of plasma above the substrate. On the other side, these characteristics of the plasma are determined by the distribution and characteristics of the electromagnetic field. Therefore the study on the distribution and characteristics of the electromagnetic field is necessary. The electromagnetic field in PECVD is simulated in this paper by means of finite element method.Due to the high and low frequency electromagnetic fields existing in PECVD, two finite element methods are introduced, which are used in the calculation of low and high frequency electromagnetic field, respectively. The electromagnetic field in PECVD chamber is simulated in high/low frequency and the simulation results are analyzed. For the specific process, the harmonic analysis of the chamber is carried on firstly using ANS YS software, and electromagnetic field distribution under low frequency is obtained. The results show that the electric field distribution is uniform except the boundary effect. Furthermore, the weak spiral magnetic field is found and it gradually decreased from the center to around. The voltage loading on the electrode is computed by the finite element analysis of RF circuit. Moreover, the intrinsic modal analysis is carried out on the cavity in PECVD with Ansoft HFSS. The electromagnetic field distribution and the resonance frequency of the corresponding modal is also obtained in this paper. In the engineering application, the standing wave effect can be weakened by proventing from the resonance. Finally, parameterized analysis is conducted on the electromagnetic field distribution of PECVD cavity, the results show that the axial position of wafer has a great influence on the electromagnetic field distribution around it.The numerical results and the conclusion obtained in this paper can provide reference for engineering design.