Fundamental Understanding of Residual Stress in Binary and Ternary Nitride Thin Films: Measurements and Modeling

非技术描述：氮化物薄膜广泛用于保护工具涂层和微电子互连等应用。然而，沉积的薄膜往往存在大量的残余应力，这可能会降低其性能或导致失效。为了控制和预测应力，需要对薄膜沉积条件和所产生的应力之间的关系有更基本的了解。这种理解是通过执行全面的测量并使用它们来开发一个可以预测不同条件下的应力的模型来实现的。这为选择加工参数提供了一种科学的方法，而不是反复试验。通过提供分析和优化薄膜用户生长过程的工具，与其他人共享此模型会对广大薄膜用户社区产生影响。接受该项目培训的学生对控制薄膜生长的动力学过程有深入的了解，这些过程在汽车零部件和半导体加工等行业中很有价值。技术细节：氮化物薄膜中的应力研究将测量与开发定量模型结合在一起。使用光学技术在薄膜沉积期间实时执行测量。系统地改变不同的工艺参数(生长速度、压力、氮气流量)，以生成一组全面的数据。对具有不同组成的二元氮化物(含单一过渡金属物种的氮化物)和三元氮化物(含两种过渡金属物种的氮化物)进行了测量。这些数据被用来根据基本的动力学机制开发一组速率方程，这些方程可以计算不同加工条件下的应力。将模型方程应用到实验中，可以为每种材料提取一组动力学参数。这对于解释数据和理解控制压力的过程是重要的。它还通过预测能够产生所需应力的参数来改变选择加工条件的方法。该模型的一个用户友好的基于网络的版本可以被其他人用来分析他们自己的结果并选择符合他们需求的最佳处理条件。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

NON-TECHNICAL DESCRIPTION: Nitride thin films are widely used in applications such as protective tool coatings and microelectronic interconnects. However, the deposited films often have large amounts of residual stress that can reduce their performance or lead to failure. A more fundamental understanding of the connection between the film deposition conditions and the resulting stress is needed in order to control and predict the stress. This understanding is achieved by performing comprehensive measurements and using them to develop a model that can predict the stress under different conditions. This provides a science-based method to choose the processing parameters instead of trial-and-error. Sharing this model with others impacts the broad community of thin film users by providing a tool to analyze and optimize their growth processes. The students who are trained on this project develop a deep understanding of the kinetic processes controlling thin film growth that are valuable in industries such as automotive components and semiconductor processing. TECHNICAL DETAILS: The research on stress in nitride thin films integrates measurements with the development of a quantitative model. The measurements are performed in real-time during the deposition of the films using an optical technique. The different processing parameters (growth rate, pressure, nitrogen flow rate) are systematically varied so that a comprehensive set of data is generated. The measurements are done on both binary nitrides (nitride with a single transition metal species) and ternary nitrides (nitride with two transition metal species) with different compositions. The data is used to develop a set of rate equations based on the underlying kinetic mechanisms that can calculate the stress for different processing conditions. Applying the model equations to the experiments allows a set of kinetic parameters to be extracted for each material. This is important for interpreting the data and understanding the processes controlling the stress. It also transforms the method of choosing processing conditions by predicting parameters that can produce the desired stress. A user-friendly web-based version of the model can be used by others to analyze their own results and select the best processing conditions for their needs.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.