One of the main issues with implementing in-situ sensor solutions for Advanced Process Controlrn(APC) applications is the integration of the sensor with the machine and the fab APC systems. All toornoften a good idea fails because of the difficulty in integrating sensor data with the tool's real-timernstate, the current process recipe and other relevant APC data.rnOne approach to overcoming this problem is to integrate a SEMI Sensor Bus network within the toolrnitself so that the sensor and the tool can easily exchange data in a real-time environment. With suchrna network, best-of-breed new sensors can be added to the tool with a minimum of custom codewriting.rnAdditionally, the sensor network would enable an intelligent sensor to inhibit the tool on arnreflex-action basis. Furthermore, a Sensor Bus framework facilitates placement of intelligentrncontrollers and data processors as close as possible to the chamber. The benefits of chamberrnsensor controllers include (I) collection and presentation of data from various sources on the toolrn(sensors, chamber actuators, etc.) at a single point, (ii) uniform time referencing and combination ofrnprocess/sensor data with framing data, and (iii) data pre-processing to remove known false readingsrnand chamber faults from conditioning and maintenance prior to sending data to the host.rnThis paper discusses the implementation of such an approach at a 300-mm facility using SEMIrnSensor Bus MODBUS TCP. The practical aspects of the project, including integration andrncommissioning aspects, will be discussed along with the advantages gained as perceived by the endrnuser, the APC integrator and the OEM. In particular, the following will be discussed:rn? Sensor Bus Implementation on PVD Deposition toolrn? Sensor Bus selectionrn? Ease of integration with the tool control systemrn? Reasons for integrating a SEMI Sensor Bus on the tool rather than using the SECS/HSMSrnportrn? Implications for eDiagnosticsrn? Integration considerationsrn? Tool-to-sensor communicationsrn? Integration with the Fab APC systemsrn? Scheduling and co-ordination with tool hook-up - on the critical pathrn? Startup and commissioning tipsrn? Cost considerationsrn? Practical examplern? Plasma arc counting on PVD chamberrn? Application illustration of the integration of sensor data with tool real-time data (RF power,rnvalve status, etc.)rnFinally, the paper discusses the lessons learned on this large project, and draws conclusionsrnregarding the overall approach to integrating in-situ sensors with tool data using SEMI Sensor Bus.
展开▼
