Patent ID: 7566634

Claim:
A method of singulating at least one chip from a stack of layers, the stack comprising a front end of line upon a substrate layer, the substrate layer having a first surface and a second surface, the front end of line being positioned on top of the first surface, and a back end of line on top of the front end of line, the method comprising: etching singulating trenches through the back end of line, through the front end of line and at least partially through the substrate layer of the stack; depositing a passivation layer on the stack provided with the etched singulating trenches, such that sidewalls of the trenches are at least partially passivated; and releasing the at least one chip from the stack of layers by reducing the thickness of the substrate layer from the second surface onwards to the bottom of the etched singulating trenches until the at least one chip is released from the stack.