Increasing die strength by etching during or after dicing

摘要

A substrate is diced using a program-controlled pulsed laser beam apparatus having an associated memory for storing a laser cutting strategy file. The file contains selected combinations of pulse rate Δt, pulse energy density E and pulse spatial overlap to machine a single layer or different types of material in different layers of the substrate while restricting damage to the layers and maximizing machining rate to produce die having predetermined die strength and yield. The file also contains data relating to the number of scans necessary using a selected combination to cut through a corresponding layer. The substrate is diced using the selected combinations. Gas handling equipment for inert or active gas may be provided for preventing or inducing chemical reactions at the substrate prior to, during or after dicing.

主权项

1. A method of dicing a semiconductor wafer having an active layer on a major surface of the semiconductor wafer, the method comprising:
mounting the semiconductor wafer on a carrier with the active layer facing away from the carrier; directing laser emission in a scan field for incidence on the major surface, the laser emission at least partially dicing the semiconductor wafer on the carrier and thereby forming an at least partially diced semiconductor wafer having material connecting adjacent die; and providing an active gas for etching from the at least partially diced semiconductor wafer on the carrier the material connecting adjacent die to remove sufficient semiconductor material from a die produced from the at least partially diced semiconductor wafer to singulate the adjacent die and improve die strength.