A Process Development Execution System (PDES) is a system, which is used by companies to perform development activities for high-tech manufacturing processes. A PDES is similar to a Manufacturing Execution System (MES) in several aspects. The central distinguishing factor is that PDESs are tailored for steering the development of a manufacturing process while MES are tailored for executing the volume production using the developed process. Therefore the focus and the toolset of a PDES is more on lower volume but higher flexibility and experimentation freedom. The tools of a MES are more focused on less variance, higher volumes, tighter control, and logistics. Both types of application software have in common that they increase traceability, productivity, and quality (for PDES the quality of the developed manufacturing process in contrast to the quality of the manufactured good (economics and accounting)/commodity for MES). Additionally both software types share functions including equipment tracking, product genealogy, labor and item tracking, costing, electronic signature capture, defect and resolution monitoring, Executive Dashboards, and other various reporting solutions.
PDES have many parts and can be deployed on various scales. From simple Work in Progress tracking to a complex solution integrated throughout an enterprise development infrastructure. The later are touching other enterprise systems like Enterprise Resource and Planning Systems (ERPs), Manufacturing Execution Systems (MESs), Product Lifecycle Management (PLMs), Supervisory, Control and Data Acquisition (SCADA) solutions and Scheduling and Planning Systems (both long-term and short-term tactical).
Example: PDES usage during semiconductor device development Edit
New ideas for manufacturing processes (for new goods/commodities or improved manufacturing) are often based on or can at least benefit from previous developments and existing recipes in use. The same is true when developing new devices e.g. a MEMS sensor or actuator. A PDES offers an easy way to access these previous developments in a structured manner. Information can be retrieved faster and previous results can be taken into account more efficiently. A PDES typically offers means to display and search result data from different viewpoints and to categorize the data according different aspects. These functionalities are applied to all result data like materials, process steps, machines, experiments, documents, pictures etc. The PDES also provides a way to relate entities belonging to the same or similar context and to explore the resulting information.
In the phase of assembling process steps to process flows a PDES can help to easily assemble, store, print, and transfer new process flows. By providing access to previously assembled process flows the designer of process flows is able to use those as building blocks or modules in the newly developed flow. The usage of standard building blocks can reduce the design time and the probability of errors drastically.
A PDES shows its real advantages in the verification phase. Knowledge (e.g. in the semiconductor device fabrication: Clean before deposition; After polymer spin-on no temperature higher than 100°C until resist is removed) have a form that can be expressed in a computer readable way; they can be expressed in rules. If a domain expert enters the rules for his/her process steps they can be used by all engineers to check newly developed process flows. For a PDES that means it has to be able to (1) manage rules (2) connect rules with Boolean terms (and, or, not) and (3) to check process flows using these rules. This rule check verifies the principle manufacturability of a newly designed manufacturing flow.
The processing rule check gives no indication on the functionality or even the structure of the produced good or device. In the area of semiconductor device fabrication the techniques of semiconductor process simulation / TCAD can provide at least an idea about the produced structures. To support this ’virtual fabrication’ a PDES is able to manage simulation models for process steps. Usually the simulation results are seen as standalone data. To rectify this situation PDESs are able to manage the result files in combination with the process flow, too. This enables the engineer to easily compare the expected results with the simulated outcome. The knowledge gained from the comparison can again be used to improve the simulation model.
After the virtual verification the device is produced in an experimental fabrication environment. A PDES allows to transfer the process flow to the fabrication environment (e.g. in semiconductor: FAB). This can be done by simply printing out a runcard for the operator or by interfacing to the MES of the facility. On the other hand a PDES is able to manage and document last minute changes to the flow like parameter adjustments during the fabrication. During and after processing a lot of measurements are done. The results of these measurements are often produced in the form of files like pictures or simple text files containing rows and columns of data. The PDES is able to manage these files, to link related results together, and to manage different versions of certain files (e.g. reports). Paired with flexible text and graphical retrieval and search methods a PDES provides mechanism to view and assess the accumulated data, information, and knowledge from different perspectives. It provides insight into previous developments concerning information aspects as well as for time aspects. Finally more and more development activities in the industry are a collaborative effort. This leads to the need to exchange the information between the partners or to transfer process IP from a vendor to a customer. The PDESs support this transfer while being selective to protect the IPR of the company.
D. Ortloff, J. Popp, T. Schmidt, and R. Brück. Process Development Support Environment: A tool SUITE TO ENGINEER MANUFACTURING SEQUENCES In International Journal of Nanomanufacturing, “Recent Developments and Innovations in NEMS/MEMS devices”, 2007
T. Schmidt, K. Hahn, T. Binder, J. Popp, A. Wagener, and R. Brück. OPTIMIZATION OF MEMS FABRICATION PROCESS DESIGN BY VIRTUAL EXPERIMENTS. In Proceedings of SPIE: Micro- and Nanotechnology: Materials, Processes, Packaging, and Systems III, Adelaide, volume 6415, 2006. Smart Materials, Nano and Micro-Smart Systems 2006.
See also Edit
- Manufacturing Process Management
- Manufacturing Execution System
- Semiconductor device fabrication