lithoAPC Modules

lithoAPC Run to Run

Features

lithoAPC combines a modern interface with a clear, workflow-oriented user experience. Engineers can move through complex APC functions quickly because the architecture is structured, modular, and consistent.

Intuitive user interface

All modules are integrated into the APC desktop application. The interface combines the functions required to configure, monitor, and control APC workflows. In detail, this includes:

visualize measurement and process data
create, delete, and configure master data
control the status of master data
visualize and compare all analysis results and intermediate information including
- systematic failure
- value and residual statistics
- residuals
trigger manual analysis for single or selected runs
edit run context information or measurement values
access wafer visualizations
visualize the process timeline in diagrams
access user management and system capabilities
connect to any lithoAPC server in the network
export and import functionality
copy table data

The ongoing development of the system will produce frequent new modules and new features accessible in the user interface.

Screenshot RuntoRun View

Master data and parameterization

lithoAPC is fully configurable through master data. Master data can define instructions or required analysis information such as wafer layouts, target sets, and parameter models.
New master data implementations and customer-specific master databases can be integrated to extend system functionality.
Master data can be parameterized, and these parameters are evaluated dynamically during analysis. Values are resolved when the run is requested.

LVHM production support

Low-volume, high-mix fabs have specific requirements. lithoAPC is designed for these environments, combining strong production performance with an efficient engineering workflow.

Optimized throughput

lithoAPC focuses on high-quality prediction of offset values and exposure settings for process tools. Modern filtering technology selects the best historical exposures to calculate optimized offset values and exposure energy.
In logic fabs, pilot wafers are often required during product ramp-up and after tool maintenance. lithoAPC addresses these use cases and helps reduce or avoid pilot-wafer runs.

Real-time support

lithoAPC always works with current production data. Some startup-value predictions analyze six months or more of history, so calculation time directly affects tool time. lithoAPC provides results quickly, with 98% of requests completed in under one second and the remaining 2% in under three seconds.

Configurable R2R controller

The integrated R2R controller is highly configurable and supports common photolithography use cases. Even demanding exposure workflows become manageable, from R2R configuration to startup-value generation.

Extensible, modular system architecture

lithoAPC is expandable. All features are implemented based on a modular architecture and are dynamically bind during run time. New features can be easily integrated into the system – independent, whether they are provided by BlueLine AG, the IT department of the FAB or any third party.

Advanced data merge

Incoming data is automatically merged with existing process information for the same lot and layer. The merge algorithm recognizes the correct sequence of exposures and measurements. Even complex use cases like tool aborts, reworks and splits are handled by the software.

Default values

Standard prediction

lithoAPC allows to calculate starting values for the process tool. This calculation is based on reference runs with similar process conditions. The standard configuration selects a defined number of reference runs. Based on these runs, a R2R controller calculates the optimum starting parameters using the configured controller. By default an EWMA controller is used (enhanced weighted moving average). This controller can be replaced with other approaches.
The system allows to run several controllers in parallel. Each controller will manage a predefined subset of all starting parameters. This offers the greatest flexibility for all applications in photo lithography.

User-defined R2R levels with fallback

The system can be configured with R2R levels. With this approach, the entire process can be described from a R2R perspective. Especially for high mix production lines and tool mix without dedication, the R2R level support groups e.g. for similar tools or products. This approach has proven itself over many years in advanced logic fabs. The use of R2R levels provides full access to all filter functions like

flexible selection of filter criteria
dynamic filter criteria (dynamically
evaluated
based on customer sources)
virtual grouping
grouping by target or gradient values

Selectable optimization strategy (default: EWMA)

The selected historical runs are optimized with an assigned optimizer. EWMA is used by default, but users can replace it with another optimizer.

Control flow using UseApc flag

The R2R functionality is enabled by default and can be disabled for selected processes. If APC is disabled, the system uses default values.

Virtual grouping

There are logic products, which are identical up to a certain process layer. Technically those products fit into the same controller group – but due to different product names these products often are handled completely independent of each other. To avoid pilot-wafer runs and in order to learn from the other products within the group, lithoAPC enables the declaration of virtual product groups.

Unique 2-phase streaming data filter

Standard database filtering is applied at the database level. A second system-level filter handles advanced criteria such as dynamic context information. To ensure fast response times, a live database stream is used for filters, outlier checks, and validations. The filter supports complex criteria based on the current run context as well on any context information in the MES system. It includes the status information, scope of time and more. Without any additional effort, the user can filter – for example – by reference layer information or a process tool.

Outlier elimination

The calculation of the startup values is based on previous runs and their optimal process conditions. The system expects a continuous distribution and tests the data quality. The outlier elimination will detect and remove all runs, which do not follow the common behavior. Outlier elimination is based on a combination of absolute outlier limits and the definition of relative tunnels.

Constraint check on start-up data

Reference data must meet a predefined minimum quality level. This quality level is defined based on rules. In case of any violation of the user-defined data range the software allows to trigger a pilot wafer to validate the process.

Use constraints

Reference data must meet a predefined minimum quality level. This quality level is defined based on rules. In case of any violation, which can be used to trigger a pilot wafer.

Full inline support for any tool and tool type combinations

The system distinguishes between different tool types. Logical controller groups are supported. Logical controllers can combine data or allows to split data into distinct groups.

Graphical user interface with direct access to data and controller configuration

The extensible user interface provides access to relevant data from any client. The platform approach supports the seamless integration of new modules.

Full traceability of all data including controller setup

The system stores all exposure and measurement activities – no data is lost. lithoAPC will assign the correct measurement to the appropriate exposure entry. Aborted exposures and re-measurements are still stored in the database and provide a complete, unfiltered view of the activities in photo lithography. The existing complete timeline allows to simulate the process with changed process setup for any time frame in the past.

Reset management

Some process issues require selected runs to be disabled. Such runs are never used for any calculation. But these runs are still stored and visible in the user interface.

Charting

All charting is handled by a dedicated Statistics module. It supports diagram templates for multiple visualization types and can combine analysis data with R2R data. Finally, the templates can be called from the analysis or R2R modules to visualize the currently selected runs.

This template-based approach is efficient and flexible. It supports advanced diagramming features like:

various diagramming types
scatter plot
box plot
pie charts
bar plot
probability plot
table output
event timeline
histogram and normal
distribution chart

Data can also be grouped into separate charts or series based on the run context.

Gradient monitor

lithoAPC provides capabilities to monitor and upgrade the gradient information. This includes comparing runs from different processes and their behavior and finding similarities and differences. The effort for test runs to update the gradient can be reduced and the production quality can be increased.

Integrated baseline correction

The integrated baseline correction is an advanced feature. Process parameters are not only subject of process behavior. There are also dependencies on the substrate, maintenance activities, resist batches or mask size. Often the impact is just an offset (bias) to the initial baseline. lithoAPC allows to specify such baseline offsets. With this information all available data can be used to predict new starting values even if the data are at different baseline levels. There is no need to delete any data and there is no need to run additional any pilot wafers.

Best-matching view

Different master data are implemented as look-up tables and allow the definition of parameters.
The parameters are each assigned to a set of context values that correspond to the respective processes.
The “Best Matching View” provides a quick overview of the lookup tables and the parameters for a specific run.

Source-code option

Every APC solution is a critical part of semiconductor production. This concerns both the availability of the APC solution and the support for new requirements. We offer a source-code option for the APC solution, which allows you to integrate your own modules, implement new functions and, if required, continue to develop the solution independently.

lithoAPC Critical Dimension

Features

lithoAPC impresses with its modern design and user-friendly interface.
Engineers can navigate features quickly because the architecture is structured and consistent.