Electrical Engineering
      and Computer Sciences

Electrical Engineering and Computer Sciences

COLLEGE OF ENGINEERING

UC Berkeley

Process-Flow Specification and Dynamic Run Modification for Semiconductor Manufacturing

Christopher J. Hegarty

EECS Department
University of California, Berkeley
Technical Report No. UCB/ERL M91/40
1991

This dissertation describes applications of a semi- conductor process representation to a factory control system for a computer-integrated manufacturing (CIM) system. The control system, which includes work in progress (WIP) and run management systems, uses a distributed heterogenous database to store all information. The database contains information about the fabrication facility, processes, work in progress, test data, inventory, orders, personnel, and products. The process representation used by the WIP system is the Berkeley Process-Flow Language (BPFL). BPFL is designed to allow all information about a process to be merged into a common specification. This information includes the equipment, recipes, and parameters used to manufacture semiconductors, resource requirements needed for scheduling, and modelling parameters required for process simulation. Different programs, called interpreters, read a BPFL program and perform a task. For example, a process-check interpreter reads a BPFL program and checks that it does not violate processing rules. The WIP system is another example of an interpreter. BPFL is an object-oriented language with abstractions defined specifically for semiconductor manufacturing such as lots, wafers, material, equipment, and wafer profiles. The language provides control structures designed for common processing activities such as lot splits and merges, equipment and operator communication, timing constraints, conditional control-flow, and rework loops. An exception handling mechanism is provided to allow processes to respond to unexpected conditions (e.g., equipment failure). The language is designed to separate facility-specific information from the process specification to make it easier to change equipment in a facility or move processes between facilities. BPFL and the WIP system make implementation of feedback and feedforward process control possible because data is stored in the shared database and processes coded in BPFL can access the database. The WIP system supports equipment interfacing for automatic recipe execution and monitoring. The system is software fault- tolerant so that computer system failures will not cause loss of data. The run-management system allow active runs to be modified. For example, process flows may be edited while a run is active, and lots may be moved between runs. A software version control system maintains libraries of process-flow procedures to control process revisions.

Advisor: Lawrence A. Rowe


BibTeX citation:

@phdthesis{Hegarty:M91/40,
    Author = {Hegarty, Christopher J.},
    Title = {Process-Flow Specification and Dynamic Run Modification for Semiconductor Manufacturing},
    School = {EECS Department, University of California, Berkeley},
    Year = {1991},
    URL = {http://www.eecs.berkeley.edu/Pubs/TechRpts/1991/1753.html},
    Number = {UCB/ERL M91/40},
    Abstract = {This dissertation describes applications of a semi- conductor process representation to a factory control system for a computer-integrated manufacturing (CIM) system. The control system, which includes work in progress (WIP) and run management systems, uses a distributed heterogenous database to store all information. The database contains information about the fabrication facility, processes, work in progress, test data, inventory, orders, personnel, and products. The process representation used by the WIP system is the Berkeley Process-Flow Language (BPFL). BPFL is designed to allow all information about a process to be merged into a common specification. This information includes the equipment, recipes, and parameters used to manufacture semiconductors, resource requirements needed for scheduling, and modelling parameters required for process simulation. Different programs, called interpreters, read a BPFL program and perform a task. For example, a process-check interpreter reads a BPFL program and checks that it does not violate processing rules. The WIP system is another example of an interpreter. BPFL is an object-oriented language with abstractions defined specifically for semiconductor manufacturing such as lots, wafers, material, equipment, and wafer profiles. The language provides control structures designed for common processing activities such as lot splits and merges, equipment and operator communication, timing constraints, conditional control-flow, and rework loops. An exception handling mechanism is provided to allow processes to respond to unexpected conditions (e.g., equipment failure). The language is designed to separate facility-specific information from the process specification to make it easier to change equipment in a facility or move processes between facilities. BPFL and the WIP system make implementation of feedback and feedforward process control possible because data is stored in the shared database and processes coded in BPFL can access the database. The WIP system supports equipment interfacing for automatic recipe execution and monitoring. The system is software fault- tolerant so that computer system failures will not cause loss of data. The run-management system allow active runs to be modified. For example, process flows may be edited while a run is active, and lots may be moved between runs. A software version control system maintains libraries of process-flow procedures to control process revisions.}
}

EndNote citation:

%0 Thesis
%A Hegarty, Christopher J.
%T Process-Flow Specification and Dynamic Run Modification for Semiconductor Manufacturing
%I EECS Department, University of California, Berkeley
%D 1991
%@ UCB/ERL M91/40
%U http://www.eecs.berkeley.edu/Pubs/TechRpts/1991/1753.html
%F Hegarty:M91/40