18906945. Method for Thinning a Semiconductor Substrate (IMEC VZW)

Method for Thinning a Semiconductor Substrate

Organization Name

IMEC VZW

Inventor(s)

Eric Beyne of Heverlee BE

Liesbeth Witters of Lubbeek BE

Method for Thinning a Semiconductor Substrate

This abstract first appeared for US patent application 18906945 titled 'Method for Thinning a Semiconductor Substrate

Original Abstract Submitted

A layer of semiconductor devices is produced on the frontside of a crystalline semiconductor substrate, in regions separated by dielectric-filled cavities formed previously. Additional layers are then formed on the device layer. The substrate is then flipped and bonded face down to a second substrate, following by the thinning of the crystalline first substrate from the backside. The thinning proceeds as far as possible without removing the full thickness of the first substrate anywhere across its surface. After this, an anisotropic etch is performed to remove additional material of the first substrate. The in-plane dimensions of the device regions separated by the dielectric-filled cavities are specified so that the anisotropic etch is stopped by a crystallographic plane of the substrate material or by the dielectric material in the cavities, before it can reach the devices on the frontside.