TestScape-SPC is targeted to chip manufacturers who want to insure the highest quality of product from their test operations.
The system collects data in real-time from the user's automatic testers and monitors that data for abnormal trends. Statistical process control rules, or "controls," are defined by the users via a flexible user interface. Controls are specific for products of interest. A variety of SPC algorithms are available to be used as the basis for the monitoring rule.
The diagram below illustrates a Shewhart control chart with "short term" rules, also known as WECO rules. SQC Online is a good source of information about these rules. See legend in blocks to the right that explain why the rule was triggered.
Other typical controls useful to product engineering and quality control include:
- Low yield
- H/W bin limits
- S/W bin limits
- Statistical trends (stddev, mean, etc.)
- Site-site variation
- Test time
Real-time monitoring detects issues that cannot otherwise be detected during production. Early detection reduces down time, excessive scrap and most importantly, quality slips that may impact your customers.
Unwanted trends generate "triggers" and triggers initiate alerts or "events." Users will minimize overloading the production system with excessive alerts by using the built-in simulation tool that applies newly created rules to recent production data in order to show what will happen when released to production.
A comprehensive event disposition subsystem is an integral part of TestScape-SPC. Events define the "actions to be taken." Open events are logged until the assigned owner "dispositions" the event. A management dashboard tracks the open, "in process" and closed events to provide continuous feedback on team performance. The dashboard includes "time to respond" and "time to close" as well.
Because the data acquisition is performed by Salland's SwifTest, test data can be monitored from all commercial testers as well as legacy or proprietary hardware. Installation is non-intrusive to your operations flow and integrates seamlessly with your IT infrastructure.
TestScape-SPC can be deployed to multiple test floors. In fact, SPC controls can be defined in different ways for different test floors on the same product (device types.) The system has been successfully installed on hundreds of testers at multiple test floors. It is supported worldwide by Salland Engineering.