Abstract: The current invention presents a method for thinning wafers. The method uses a two-step process, whereby first the carrier wafer (2) is thinned and in a second step the device wafer (1) is thinned. The method is based on imprinting the combined thickness non-uniformities of carrier (2) and glue layer (3) essentially on the carrier (2), with a resulting low TTV of the wafer (100) after thinning.

Abstract: A method is provided for producing 3D structures in a semiconductor substrate using Deep Reactive Ion Etching (DRIE), comprising at least the steps of: providing a substrate, and then grinding the backside of the substrate in order to achieve a thinned substrate, wherein extrusions and native oxides are left after said grinding step, and then performing a surface treatment selected from the group consisting of a wet etching step and a dry etching step in order to remove at least said native oxides and extrusions on the surface of said backside of the substrate which are causes for the grass formation during subsequent etching, and then performing deep reactive ion etching in order to achieve 3D vias.

Abstract: The current invention presents a method for thinning wafers. The method uses a two-step process, whereby first the carrier wafer (2) is thinned and in a second step the device wafer (1) is thinned. The method is based on imprinting the combined thickness non-uniformities of carrier (2) and glue layer (3) essentially on the carrier (2), with a resulting low TTV of the wafer (100) after thinning.