Using yieldHUB to Resolve a Potentially Disastrous Customer Return Challenge



In a defining moment a client of yieldHUB, with one major product in their portfolio, faced an issue with a customer return for the product. For confidentiality purposes, the identity of the client remains undisclosed. The following story highlights a key capability of yieldHUB that helped prevent a financial crisis that could have cost millions of dollars to the customer.

The Predicament

After receiving the returned die, our customer checked it again using yieldHUB's database. With yieldHUB's traceability, they could quickly see the die's production data by entering the chip's ID.

The die met all data-sheet criteria when re-tested in the lab and performed similarly to its original test production phase, considering standard variations. However, the cause of the return, an unforeseen issue, needed to be verified.

There was, as reported by their customer, an unexpected interaction within the die, which was neither predicted nor documented in the datasheet, hence never tested. This caused the die to eventually fail in its real-world application. This interaction was replicated in the lab by our customer through a new test. The new test analyzed multiple channels’ data together, revealing that if multiple channels for the chip had specific outputs under a certain condition, then the chip caused distortion. The condition itself had always been tested for each channel, but not the relationship between the channels for that result. 

The Potential Impact

This phenomenon of interaction raised concerns for our client's customer about potential future issues with other chips for the same product that they had bought and continued to buy in large quantities, jeopardizing their entire business relationship with their customer.

Furthermore, our client worried that this unforeseen interaction could affect numerous applications across various customers, potentially leading to a wave of returns and tarnishing their reputation with severe consequences for their business, attention at the highest level of the company.

With thousands of wafers of the product tested and sold and this scenario not included in production testing, the situation pointed towards a massive recall of millions of chips - a dire prospect.

The Solution

Nevertheless, the test engineers, proficient with the yieldHUB platform, implemented a “virtual” test on the database that used multiple channel results together for each die to replicate and identify the issue. This was done all within an afternoon, automatically scouring through millions of chips for their performance against this virtual multi-channel “interaction test”.

Among the extensive data evaluated, the issue was isolated to a specific wafer lot from among hundreds and hundreds tested over the preceding three years. Utilizing the platform's traceability feature in conjunction with their customer delivery database, our client successfully identified the impacted customers and facilitated the replacement of the affected chips with ones that passed the newly instituted virtual test. This proactive measure was (within minutes) integrated into the yieldHUB platform for all future lots, eliminating the need for modifications to existing test programs, thereby streamlining the resolution process. Any future wafers exhibiting the interactions would not leave the factory.

The Strategic Impact

This episode not only reinforced the client's stature within their customer base but also safeguarded their business's integrity, underscoring the indispensable role of yieldHUB in navigating and resolving certain complex semiconductor industry challenges. The subsequent acquisition of our customer’s business for a substantial sum underscores the strategic value of yieldHUB's solution in the semiconductor industry.