Kp Yan

ESD concerns in sawing wafers with discrete semiconductor devices

Wafers with discrete semiconductor devices are sawn without CO2 bubbling. On one hand, there are claims that wafer sawing process using Dl-water without CO2 bubbling is not the state of the art process. On the other hand, there is a major blocking point for the introduction of CO2 bubbling in discrete devices wafer sawing process. Because discrete device wafers have as many as 300K chips on a single 6-inch wafer. Therefore the sawing process requires as long as 2.5 hours to process a wafer. The use of DI water in the sawing process results in severe corrosion issues. Investigations are conducted and the results are presented.semiconductor wafer sawing process

Influence of machine configuration on EOS damage during wafer cleaning process

An investigation was carried out on the charging voltage of deionized (DI) water during wafer cleaning at wafer sawing process, since it was supposed to be the root cause for EOS damages during semiconductor production. The charging voltage was measured using a non-contact electrostatic field meter. It was found that the positioning of the water filter influenced the amount of charging voltage of DI water.