Bare chip taking-out method

Abstract

The invention provides a bare chip taking-out method. The bare chip taking-out method comprises the following steps that solder balls on the back face of a sample are removed; the back face of the sample is attached to a grinding jig, and the sample is flattened through a flattener; grinding the front surface of the sample, removing the part positioned on the front surface of the target bare chip, and reserving the part of the bonding film positioned on the front surface of the target bare chip and the lead positioned in the part; the front face of the sample is attached to a grinding jig, and the sample is flattened through a flattener; grinding the back surface of the sample, removing the part on the back surface of the target bare chip, and retaining a layer of bonding film on the back surface of the target bare chip; removing the residual bonding film and packaging material of the sample to obtain a target bare chip; and attaching the back surface of the target bare chip to the glass slide to complete the taking-out of the target bare chip.

Description

technical field [0001] The invention relates to the technical field of detection of integrated circuits, in particular to a method for taking out a bare chip. Background technique [0002] In the integrated circuit packaging structure, in order to increase the capacity per unit area, the packaging is usually performed in a stacked manner. At present, in the detection of integrated circuit packaging structures, the location of failure hotspots can only be accurately located for the die on the current layer. When the die stacked on the lower layer fails, the failure point cannot be located. In order to realize the failure location of the lower die, the lower die must be used to solder the integrated circuit die while keeping the original electrical properties unchanged. Chip circuit board) electrical properties, take out the bare chip, and then do failure location. Among them, the existing die removal method is to use high-temperature fuming nitric acid for a long time (more...

AI Technical Summary

Problems solved by technology

Among them, the existing die removal method is to use high-temperature fuming nitric acid for a long time (more than 1h) to separate the multi-layered die. Since the thickness of the stacked die is ultra-thin (about 50 μm), it will cause the die to be broken. Cracks and circuit board corrosion, resulting in the inability to detect electrical

In order to alleviate the above problems, although the grinding method can be used to grind down to the target die on the lower layer to reduce the soaking time, however, the traditional hand-held grinding disc still has the problem of a large level difference (about 30 μm or more) on the surface of the sample

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