Wafer Sort is a process where a die is tested electrically while still in wafer form.

Wafer Sort process done with the presence of equipment called wafer prober and Tester. A wafer prober is an equipment where the wafers will be handled inside by the prober to be placed on a platform called chuck to be probed by a probe card. Probe Card is a tool which fixed on a prober and connected to a Tester. Tester is the equipment to process the data and provide the probing results for the wafers probed. A wafer Map will be provided by Foundry which resemble the actual wafer. After wafer sort process this map will be marked accordingly to identify the pass and fail dies by Tester Equipment which will be sent to next process later on.

Wafer Sort Process is very crucial process because the results will indicate the number of the electrically failed dies in one lot. This data will be used by Foundry to see the relative problem in their process to and also for Assembly process to identify which dies to be picked for die attach process.