Die Attach Testing in Production:
Manual or Automatic Device Handling Capability
Die attach testing provides a nearly instantaneous evaluation-test of device thermal properties associated with variations in the manufacturing process. Devices manufactured with internal thermal flaws in construction are prone to premature failure due to elevated junction temperatures and can be eliminated using die attach testing. The Analysis Tech Phase 12 offers many features for die attach testing in production environments ranging from hundreds to thousands of parts per hour. Flexible on-screen test-controls allow convenient shifting between manual and automatic test modes.
Die attach testing provides a nearly instantaneous evaluation-test of device thermal properties associated with variations in the manufacturing process. Devices manufactured with internal thermal flaws in construction are prone to premature failure due to elevated junction temperatures and can be eliminated using die attach testing. The Analysis Tech Phase 12 offers many features for die attach testing in production environments ranging from hundreds to thousands of parts per hour. Flexible on-screen test-controls allow convenient shifting between manual and automatic test modes.
Given the nearly instantaneous nature of the die attach test, the loading/unloading of parts controls the overall flow of testing. The test cycle is comprised of inserting a part into the test fixture, testing, removal of the tested part, sorting based on the test result, and then repeating the cycle with a new part. For low-volume testing, manual handling of parts is typical used, averaging 400-800 parts per hour, although this can vary widely depending on the nature of the devices and the efficiency of the test setup. The Phase 12 Thermal Analyzer provides a convenient user interface for manual testing including data storage, editing, pass/fail criteria and manual binning controls for categorizing devices based on the die attach quality. One on-screen button click provides a complete histogram of the test results.
For higher testing rates or large test lots, some type of mechanized part feeding and handling is desirable. There is a wide variety of such mechanisms from manually operated mechanisms to fully automated transfer systems. The Phase 12 Thermal Analyzer offers a range of flexible interface capabilities to seamlessly coordinate testing and device transfer for semi-automatic to fully automatic die attach testing.
In fully automatic test mode, tests are initially setup using the same procedure as in manual testing. Once the handler is loaded with parts and the analyzer readied, clicking an on-screen button starts the cycle of load, test, unload, bin-sort, and repeat. This cycle of testing rotates between the analyzer and the handler with the analyzer detecting the "ready to test" signal from the handler, testing the loaded part, then sending the handler commands for bin sorting and reloading. Error conditions for jammed or inoperative parts are detected and cleared if possible. After multiple unsuccessful clear attempts, the analyzer reverts to manual mode reporting the appropriate error condition and waiting for operator intervention. The design of the automatic handler interface features a user-controlled optimization table which allows adjustment of the handler-signal-timing for maximum test through-put.
The Phase 12 Thermal Analyzer can also accurately determine the optimal heating duration using the heating characterization test method. Essentially, a "die attach" test can be "tuned" to probe a particular internal component interface by selecting the correct heating duration. This is commonly the die attach but could alternatively be some other thermal interface. Such tests are specific and highly sensitive to the thermal performance of the component interface of interest and are generally much more sensitive then steady state thermal resistance testing. Product die-attach testing is a direct and effective means for ensuring thermally consistent device production or selection.