The semiconductor manufacturing industry is known for its complex processes that span several weeks and involve hundreds of operations. This article proposes a scalable, machine learning-based framework that uses this wealth of data generated during these processes to predict the Final Test (FT) yield at the wafer fabrication stage. The objective of this new framework is to improve operational efficiency and reduce production costs.
The Importance of Yield in the Semiconductor Industry
Semiconductors are the lifeblood of modern digital technologies, powering everything from mobile devices to autonomous vehicles. The precision required during their manufacturing process is paramount. The manufacturing yield, which refers to the proportion of chips that meet the necessary specifications to be sold, plays a critical role in the industry. Every increment in manufacturing yield results in significant savings, making yield enhancement a key focus for semiconductor manufacturers.
The Challenges of Data Utilization in the Semiconductor Industry
Semiconductor manufacturing processes generate a wealth of data. However, this data is often not effectively used due to its sheer volume and complexity. It comprises a variety of numerical and categorical information, each piece related to different processes, materials, and operational parameters. Manual filtering of this data is time-consuming, and it can be easy to overlook important insights that could inform strategies for enhancing yield.
Yield Prediction: A Machine Learning Approach
In the semiconductor manufacturing process, predicting yield is traditionally complex due to the vast, diverse data generated. However, with machine learning advancements, we propose a scalable framework to efficiently handle this data. It uses Gaussian Mixture Models, One Hot Encoder, and Label Encoder to process numerical and categorical data, enabling robust yield predictions. The framework allows for automatic data processing without prior knowledge of low yield causes, reducing the need for manual filtering. Our model’s versatility in handling different data types leads to an efficient, accurate yield prediction process, revolutionizing the traditional approach.
The Data Pre-processing Techniques
We propose a scalable, machine learning-based framework that can process, interpret, and model this diverse data. Our framework applies data pre-processing techniques like Gaussian Mixture Models (GMMs) for approximation of distributions, One Hot Encoder for categorical features, and Label Encoder for feature labeling. These techniques enable the model to handle continuous data that may not fit a standard distribution and transform categorical data into a machine learning algorithm-friendly format.
Yield Management Software (YMS) Solutions
Our framework includes yield management software (YMS) solutions that automatically process and interpret the voluminous semiconductor data, negating the need for manual filtering. These yms solutions are crucial in identifying causes of yield loss and developing strategies for yield enhancement systems.
The Power of Ensemble Learning
The model utilizes ensemble learning, which combines multiple learning algorithms to achieve superior predictive performance. The model is trained on several product lines and can handle binary and multi-class problems. It also provides automated feature importance and sensitivity analysis.
Leveraging Data for Advanced Yield Analysis
In semiconductor manufacturing, effectively leveraging data can lead to significant advancements in yield analysis. Our machine learning framework capitalizes on the massive amounts of data generated during production to perform predictive modeling of Final Test (FT) yield at early stages. This proactive approach allows for timely detection of yield-related issues and implementation of corrective actions, reducing yield loss. The framework can predict output yield across multiple product lines and handle diverse types of manufacturing data. This not only enhances its versatility but also reduces the need for manual data filtering, making yield analysis more efficient and accurate.
Early Stage Predictive Modeling
Our machine learning-based framework represents a significant advancement in semiconductor yield analysis. By utilizing data analytics, the framework allows for predictive modeling of FT yield in the early stages of production. This means that issues affecting yield can be detected earlier, corrective actions can be implemented faster, and yield loss can be significantly reduced.
Versatility Across Product Lines
The framework can predict output yield across multiple product lines. This makes it a versatile tool for yield analysis across a wide range of products, increasing its value in the semiconductor testing industry. Moreover, it can handle different types of manufacturing data, making it an adaptable tool for different manufacturing parameters.
Broadening the Scope: Utilizing Wafer Acceptance Test Data
A novel feature of our model is the inclusion of Wafer Acceptance Test (WAT) data for predicting Final Test yield. WAT data, typically used for process monitoring and control, has been underutilized in yield prediction. By incorporating WAT data into yield prediction, our model provides a broader understanding of the process parameters that affect FT yield, leading to more accurate and robust predictions.
In the intensely competitive semiconductor manufacturing industry, maximizing yield is critical for improving operational efficiency and reducing production costs. Our scalable framework, leveraging the power of machine learning and data analytics, provides a comprehensive, automated solution to predict FT yield in the early stages of production. With its ability to handle various types of manufacturing data, predict yield across multiple product lines, and incorporate WAT data in yield prediction, our framework promises significant advancements in enhancing yield in the semiconductor manufacturing industry.
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