Sequence of a Die/Wafer Order with Testing

In the event the customer requires special testing or processing of an order the same sequence would apply with the exception that the shipment could be diverted directly to the third-party tester or processor. Regardless of where the products are shipped (directly to the customer or to a third party) DD & S will invoice the customer for the entire lot at the time of shipment and expect payment on the terms specified in the customer Purchase Order. DD & S will not finance the cost of the lot while the customer is proving its acceptability of the intended application. Thus, the customer assumes the risk of yield loss and/or device performance in the end application for such up-screening, special processing and other stresses applied beyond the commercial limits.

With this sequence of events in mind, one can understand that conventional Lot Acceptance Testing (LAT) as is customarily applied to packaged parts for military or spacecraft use is not directly applicable for commercial die and wafer purchases. However, this does not preclude the customer from applying some of the more critical criteria to their unpackaged devices, providing the customer understands and accepts the risks described above. Some of the applicable third party processing of die and wafers include the following:

(a) Visual inspection of the die/wafer lot to any desired level of quality (e.g. step coverage, contamination, etc.).

(b) Probe testing of individual die or entire wafers at elevated temperatures.

(c) Specialized testing of timing parameters under extreme bias conditions.

(d) Wafer “bumping” for flip-chip mounting applications.

(e) Scribing and breaking (sawing) wafers into die.

(f) Repackaging for shipment to the customer.

(g) Construction Analysis to understand the materials and interfaces within the device.

(h) Scanning Electron Microscope (SEM) analysis for process validation.

DD & S provides expert assistance with the design and implementation of these third-party activities. Such assistance is a special service beyond the basic cost of the die or wafers and is quoted as a separate item upon request.


		Test & Processing Design				Multi Die Modules & Stacks