Optimal+ provides a suite of IIoT solutions that collect product test data from across your distributed supply chain, providing you with the cleanest and most accurate data sets possible for making time-sensitive yield recovery decisions. From the early detection of defective parts to reclaiming devices, boards and components wrongly labeled “bad”, we provide you with 24/7 rules-based product analytics to optimize yield for HVM.

Manufacturing intelligence to maximize Yield:

Clean, reliable data

Our comprehensive database aggregates a wealth of information from test operations and powers data analytic tools that provide lightning fast access to actionable information.

Cross-facility scrutiny

Supported by virtually every foundry and OSAT that serves the semiconductor ecosystem and rapidly expanding to the electronics supply chain gives Optimal+ customers the unique advantage of being able to compare product yield results and trends across their globally-dispersed test fleets. 

Early detection with real-time impact

Track, capture and detect user-defined statistical changes in your products’ manufacturing, test or assembly processes to enable corrective measures before they become costly. Optimal+ employs a 24/7 rules engine which catches problems as soon as they start to occur, triggering alerts and process control actions that are defined by the manufacturing operations team.

Powerful customized analysis

Our feature-rich UI functionality enables users to build and design their own customized templates to drive powerful and intuitive product analysis features for intelligent actionable insights. Users can also automatically generate real-time reports and distribute to other stakeholders.

“We were able to achieve significant improvements in product yield and quality”


John Docherty

Senior VP, Global Operations
AMD

Examples

Maximizing Yield through Probecard Performance Analysis
Finding the Issue
A high-level product-based report shows that a product is achieving lower than expected yield and higher than expected retest rates.

Performing the Analysis
By drilling down to individual tester performance within the Optimal+ solution the engineer is able to identify a specific probe card, which is causing the issue within a matter of minutes. The test house is notified and the probe card is removed for inspection.

Preventing Future Recurrences
A rule is created to automatically catch lots exhibiting high site-to-site yield discrepancies. The next time this problem occurs, an email alert can immediately be sent to the user so that the problem can be immediately resolved.

Maximizing_Yield

Step 1 – Analyzing a probecard shows site 3 with consistently low yield

 

site-to-site-deviations

Step 2 – Creating a rule to catch site-to-site deviations for this product

 

alert

Step 3 – Receiving an alert when the problem next occurs
img_2 Maximizing Yield through Probecard Performance Analysis

Saving Yield by Managing Probe Cards
The Challenge
A large fabless company tests a number of different products at various test houses around the globe. Each test house maintains its own supply of probe cards for each of the tested products. Using the Optimal+ solution, the fabless company detects that significant yield loss is attributed to poorly maintained probe cards. The company wants a mechanism to alert when a probe card is nearing the end of its life span or requiring preventative maintenance, before yield loss starts to occur.

The Solution
Test data collected in the Optimal+ Database contains an accurate count of touchdowns and cleans performed by each probe card. A “target” is defined in the Optimal+ database for each individual probe card specifying the number of touchdowns at which an alert is to be triggered. When the alert is triggered, a request is sent to the supplier to perform preventative maintenance. When the probe card is re-instated, the target is updated with the new value for the next maintenance cycle. Views generated by the interface are defined to display aging probe cards together with data from probe card related rules showing issues with probe cards. In the first example, the dashboard shows rule alerts by a probe card with a summary of the top “offender” probe cards that triggered the most alarms for yield/quality issues. The second example contains information about each probe card with its performance and health status including total touchdown count, average lot yield by site, bin summary by site etc… It also shows the target spec for each probe card and its status in relation to that spec (the colored column).

 

img_2 Saving Yield by Managing Probe Cards

Uncovering Geographic Issues at Final Test
Finding the Issue
When a chip has an Electronic Chip ID (ECID) it is possible to discover wafer geography issues based on final test data. Even though parts pass at wafer sort, they fail at final test and the fallout is related to wafer geography and fab process issues. The trigger for performing this analysis is a final test parametric test that has a higher than expected failure rate. This is discovered using a failing test Pareto chart in the Optimal+ solution’s portal.

Performing the Analysis
In this example, an engineer uses the solution’s wafer map reconstruction capabilities to analyze the fallout of a parametric test performed at final test. Wafer map reconstruction is an excellent tool for yield learning analysis. The wafer clearly shows that most of the failures occur near the edge of the wafer. The impact of this issue is that failures, which could be detected at wafer sort, were deferred to final test, causing costly and unnecessary packaging of bad devices.

This issue is resolved by creating a screening test in the wafer sort process so that these problems are caught earlier. The fab is notified so that improvements can be made to the wafer manufacturing process. We call this useful capability “Data Feed Backward” – taking data from a later operation and using it for yield learning in earlier operations.

 

data-feed

img_2 Uncovering Geographic Issues at Final Test