Uncovering Hidden Tool and Fab Productivity
Staggering increases in device complexity and greater sophistication in production tools and techniques mean that device manufacturers are challenged more than ever to control variables, maintain productivity and refine and improve their operations to meet increasingly difficult device performance, yield, cost and time-to-market goals.
Applied Materials’ FabVantage Consulting Group was established specifically to help customers resolve their most difficult challenges. Part of the company’s Applied Global Services (AGS) business, FabVantage consulting combines the skill and knowledge of teams of seasoned fab experts with state-of-the art modeling and analysis tools, and with Applied’s deep systems and technology roots.
From a handful of engagements beginning in 2011, the FabVantage Consulting Group has now completed more than 130 unique engagements throughout the world across a range of tool types and processes, from legacy 200mm systems to leading edge 300mm tools (figure 1).
|Figure 1. Applied Materials FabVantage consulting engagements are focused on resolving manufacturing challenges across many tool types and applications.|
These consulting engagements range from a detailed focus on a single process step to larger engagements where increasing overall fab productivity is the goal. Some examples of the types of improvements FabVantage consultants uncover are reductions in particles, defects, film thickness non-uniformity and cost-of-ownership (CoO), and increases in device performance, yield, cycle times and throughput (see figure 2).
|Figure 2. Consulting engagements are designed to uncover opportunities for improvements in many areas that challenge tool and fab performance. |
The FabVantage consulting service is a response to the reality that improving tool uptime requires resolution of root cause issues causing particles, defects, and excursions, leading to excessive maintenance,” said Sanjiv Mittal, vice president and general manager of the FabVantage group. “The need for the consulting service became apparent as customers began to ask for increasingly broader solutions to more difficult problems around the quality of the devices they were producing and the productivity of their entire production lines.
“FabVantage formalizes and strengthens the collaboration with customers, especially those covered under Applied service agreements. We provide them with trusted advisors and access to a deeper mix of talent, training, experience and technology Applied can bring to the table to address these problems,” he said. “It’s a key part of the arsenal of services and hardware solutions Applied can offer to help customers find ways to increase yields and lower costs.” (See figure 3.)
|Figure 3. AGS service capabilities are enhanced with FabVantage consulting services that address a more complete portfolio of solutions for tool and factory yield, output and productivity.|
PEOPLE, KNOWLEDGE, TECHNOLOGY
There are now more than 30 dedicated FabVantage consultants, augmented by hundreds of Applied Materials process engineers and thousands of Applied customer engineers—a deep pool of talent with decades of experience and world-class expertise in analytical methods, software, sensors, controls, tools and fab operations.
In delivering consulting services, FabVantage experts employ a trove of product and process knowledge and advanced technology. For example, Applied’s vast knowledge base is a critical tool for FabVantage teams. It is an exhaustive compilation of tool performance metrics and best known methods (BKMs), containing data on each Applied tool’s entitlement for uptime, throughput, process results, and particles; BKM recipes, equipment settings, maintenance procedures, hardware configurations and software revisions for hundreds of types of process chambers; and trend charts that show process sensitivity to various controllable inputs.
Consultants also rely on advanced software technology for diagnostics, analytics and factory automation, including Applied’s Real Time Dispatcher (RTD), manufacturing execution software (MES), and equipment engineering systems (E3).
The FabVantage consulting service has also added specific technologies and experts to better address the areas of process optimization, defects, critical sensors, modeling and simulation, and to analyze tool characteristics.
ONE METHOD, THREE SPECIALIZED PRACTICES
A typical FabVantage engagement begins with a discovery session focused on identifying key customer goals and challenges. A benchmarking process is performed to compare customer data with best-in-class data from the Applied knowledge base. The next step is a formal assessment to define the problem, to clarify the situation in the fab, and then to develop a strategy to achieve improvements in targeted areas.
The FabVantage consultancy serves customers via three specialized practices: Tool Output; Yield and Predictability; and Fab Productivity and Cycle Time. Each is led by seasoned executives who are deeply experienced and intimately familiar with the issues and economics involved in running high volume production fabs with highly complex production tools and processes.
The Tool Output Practice focuses on fab tool output, variability, excursion control, baseline particle improvement, equipment clean-in-place (CIP), software analytical tools, factory design, startup and ramp.
Figure 4 shows the results of one customer engagement, in which FabVantage Tool Output consultants were able to help a customer increase polysilicon deposition throughput by 18 percent and reduce particle-related wafer scrap by 80 percent.
|Figure 4. One customer was experiencing low throughput (TPT) and high defects in a chamber used for polysilicon deposition. FabVantage consultants were able to help the customer increase tool throughput by 18 percent and reduce particle-related wafer scrap by 80 percent.|
Yield and Predictability
The FabVantage Yield and Predictability Practice focuses on excursions, matching, process control, defects, predictability and yield-based fault detection and classification (FDC).
A typical customer engagement addressed by this practice is shown in Figure 5. The FabVantage team identified and recommended process control improvements for a Centura epitaxial deposition tool which, when implemented, resulted in a reduction in process qualification downtime of more than 60 percent. Thickness non-uniformity was also reduced by greater than 50 percent.
|Figure 5. A customer was experiencing high within-wafer thickness non-uniformity and high qualification downtime with a Centura epitaxial deposition tool. Consultants from the FabVantage Yield and Predictability Practice were able to help the customer reduce thickness non-uniformity by more than 50 percent, and process qualification downtime by more than 60 percent, through improvements in process control.|
Fab Productivity and Cycle Time
The newest area of Applied Materials’ FabVantage consulting offering, the Fab Productivity Practice, helps customers increase overall efficiency and output by addressing factory-level issues such as capacity shortages, long cycle times, high wafer costs, line imbalances, high levels of work-in-process (WIP) and high variability, among others.
The Fab Productivity Practice is also engaged to help customers find ways to squeeze more capacity out of their existing fabs by increasing throughput, which can eliminate or defer the need for sizeable capital investments.
One of the techniques used by the fab productivity consultants is a multivariate data analysis that shifts the focus from individual tool factors to relationships among multiple tools and variables. This method uncovers root causes and indirect effects. Figure 6 shows the results of a multivariate statistical analysis of the performance of a group of tools. It illustrates the ability to illustrate the inter-relationships among different variables that impact cycle time. The area highlighted in (1) shows that some tools with high uptime aren’t being used, even though (2) tells us that cycle time (i.e. “lot wait time”) is strongly driven by tool utilization. Also, (3) shows that among tools having low uptime, there is a high variability in uptime.
|Figure 6. The results of a multivariate statistical analysis of the performance of a group of tools. |
Uncovering Hidden Productivity in the FabThree years on, the FabVantage team has demonstrated how combining the best technology, the deepest knowledge, and experienced experts can help customers uncover hidden productivity in the fab and solve some of their most difficult manufacturing challenges in one of the world’s most dynamic and competitive industries.