Theoretical Simulation And Experimental Validation Of Etching And Deposition

With the development of microelectronics technology, complexity of etching anddeposition chamber condition increases, especially for the plasma participation process.At present, as for the IC process design and equipment manufacturing, most of theengineer base on experience to improve the results. But this method costs a lot of timeand money. Therefore, a combination of theoretical analysis, computer simulation andexperiment verification is an efficient way to demonstrate the technology process, aswell as deeply understand the mechanism of etching and deposition. Chamber reactionconditions can also be optimized based on this. Moreover, the reaction principle can beapplied to the manufacturing process of IC devices to achieve better performance.The theoretical research includes reactor scale and feature scale parts. Moleculardynamics method was adopted to do the reactor scale analysis, and particle massconservation equation, momentum conservation and thermal equilibrium equation weresolved. Level set method was used to calculate the feature scale evolution, and level setfunctions were used. Secondly, a commercial software package CFD-ACE+wasadopted to simulate the IC process. Chemical reactions and parameters were set inCFD-ACE and CFD-TOPO modules, and also adjusted to optimize results. Thirdly, forthe experimental part, we designed different scale of critical dimensions based ondifferent substrate. Also a variety of measurements were used to analyze the quality.Etching process includes silicon and silicon dioxide substrate, an ICP method wasused. As for the silicon etching, feed gas were Cl2/Ar mixtures. We found that thechamber conditions had an impact on the flux of radical and ions to the substrate andfurther change the etch rate and anisotropic. We also analyzed the sidewall bowing andmicrotrenching effects, and figured out byproduct redeposition on the sidewall, ionenergy and angle distribution were the possible causes. As for the silicon dioxideetching, feed gas were CHF3/H2mixtures. We found that etch aspect ratio and flux ratioof radical and ions were the factors affected the final etching profile. Finally, thisetching mechanism was applied to RRAM manufacturing process, and the optimaletching time was found to optimize the device performance.Silicon dioxide deposition process was studied, and a PECVD method was used.We analyzed the reactor scale and feature scale reaction mechanism, and adjusted the source power and feed gas flow rate ratio to achieve the best film quality and stepcoverage. Surface and hole deposition were measured by SEM, AFM, FTIR and XPSetc. method to characterize the deposition properties. We found chamber conditions willinfluence the physical and chemical properties of films, and this can be a reference toimprove the deposition quality.