Singulation is a process in a semiconductor industry where high dense strips were singulated into single units. Jig saw singulation was the updated technology where strips were seated and vacuumed on a rubber nest jig during singulation. Jig saw singulation is also practical for high volume manufacturing as it demands minimal indirect materials. To cut the strips, jig alignment with the strip was measured by the machine to ensure that the rubber nest jig will not be cut and damaged while the strip is being singulated. However, with the different upstream process that the strip undergone, machine prompt frequent jig alignment errors when the machine detected that the strip saw street has high displacement with the recorded alignment of the saw street of rubber nest jig. Through this study, the authors have driven to understand the jig alignment errors occurrences as well as the assistance that can be made for the strip to be processed. The authors also included the study of the risks that might be imposed on both rubber nest jig and the affected strips, as well as the recommendations when jig alignment errors were encountered.

Shopfloor practices that when the first cut line was aligned with the hairline, actual blade cut, and saw street of the strip, the succeeding cut lines will automatically follow with the same alignment. Considering various factors that affect the condition of the strip, it was recommended to verify the succeeding cut lines of the strip to project if the hairline will still be aligned with the saw street as cutting goes on. Unfortunately, verification of succeeding cut lines was usually skipped and refer only with the first cut alignment as reference. Thus, end up risking the units for possible cutting misalignment. Cutting misalignment can be encountered when the programmed unit pitching measurement was mismatched with the actual unit pitch of the strip. However, mismatching of the unit pitch can be anticipated through y-indexing where the saw street of the strip will be verified for alignment with the hairline along the succeeding cut lines. Frequent occurrence of mismatched unit pitching was brought about by the strip condition after series of assembly processes that expands and retracts the strip. With the mentioned scenario which has been encountered from different semiconductor assembly plants, it was best to verify the y-indexing of the strip on top of verification on the first cut line alignment. Application of y-indexing verification is essential for the entrapment and correction of mismatched unit pitching. Rejection of units due to misaligned cuts can also be prevented. Assistance of operators to adjust and monitor the hairline to compensate the actual pitching was also avoided as early as first cut line verification.

Tape saw singulation is the process where a strip was mounted on the tape attached on the frame and then sawn into single units. Circular tape saw singulation only caters one panel of the two-paneled strip which was found to be consuming with the machine capacity and resources. Driven by continuously growing volumes of customer demands at the Philippines for the past two years, it was a challenge for the machine to maximize its capacity while minimizing the cost and resources. Opportunity was found on exploring the idea of dual work piece where two strip panels were catered by one circular tape frame. Dual work piece application would not only maximize the machine capability and capacity but also reduce the cost of resources consumed per strip loading. In this study, the authors have explored the workability of dual work piece cutting where two panels can be catered on one circular frame instead of the current one panel per circular frame. Dual Work Piece application was found to be effective to achieve the goal of maximizing the machine capacity while trimming down the expenses by 50% that was brought about by the resources demanded to process the strips at singulation. With the results of the study, it was recommended for the dual work piece cutting be applied and explored on growing semiconductor industry.

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After singulation process where the strips are being cut into single units, unit tray loading comes next. Unit tray loading is the process where the singulated units will be picked up from the table and then place it in a tray pocket. Z-picker assembly executes the pick and placing activity through vacuum suction. Vacuum pads were installed on the Z-picker’s vacuum pad holder area, and it contacts with the unit. Vacuum pads come with different design depending on dimension and configuration of the device in process. Pick and place process is prone for unit dislodge as it transfers the unit from one place to another. These unit dislodges will result to missing units and will be accounted for yield loss. In this study, the authors were driven to understand the Z-picker mechanism together with the effect of vacuum pad designs, aiming to find the best match that would lessen the occurrence of unit dislodges.