Unity Semiconductor Corporation

Wolfgang Alexander Iff

Alain Courteville

Michael Schöbitz

A method for characterizing structures etched in a substrate, such as a wafer is disclosed. A bottom of the structure is embedded in the substrate, the substrate having a top side in which the structures are etched and a bottom side opposite to the top side. The method includes the following steps: illuminating the bottom of at least one structure with an illumination beam issued from a light source emitting light with a wavelength adapted to be transmitted through the substrate, acquiring, with an imaging device positioned on the bottom side of said substrate, at least one image of a bottom of the at least one structure through the substrate, and measuring at least one data, called lateral data, relating to a lateral dimension of the bottom of the at least one HAR structure from the at least one acquired image. A system implementing such a method is also disclosed.

Method and a system for characterising structures through a substrate

A method for characterizing a structure etched in a first substrate surface, the structure extending along a longitudinal direction, z, into the substrate, the method implemented by a system including a light source emitting an illumination beam with a wavelength transmitted through the substrate, and an imaging device positioned to face a second substrate surface opposite the first surface, the method including illuminating at least one structure with the illumination beam, subsequently positioning an object plane of the imaging device at at least two different longitudinal positions; acquiring at least one image of the structure at each of the longitudinal positions, the images being acquired through the substrate; measuring data relating to a lateral dimension of the structure from each acquired image at each of the longitudinal positions; and determining longitudinal data relating to a longitudinal shape of the structure from the lateral data of at least two longitudinal positions.

Method and a system for characterizing structures through a substrate

A method for characterizing structures etched in a substrate, such as a wafer is disclosed. The method includes the following steps: illuminating the bottom of at least one structure with an illumination beam issued from a light source emitting light with a wavelength adapted to be transmitted through the substrate, acquiring, with an imaging device positioned on the bottom side of said substrate, at least one image of a bottom of the at least one structure through the substrate, and measuring at least one data, called lateral data, relating to a lateral dimension of the bottom of the at least one HAR structure from the at least one acquired image. A system implementing such a method is also disclosed.

A method for characterising high aspect ratio ('HAR') structures etched in a substrate includes, for at least one structure, an interferometric measurement step, carried out with a low-coherence interferometer positioned on a top surface of the substrate, for measuring with a measurement beam, at least one depth data relating to a depth of the HAR structure, and a first adjusting step for adjusting a diameter, at the top surface, of the measurement beam according to at least one top critical dimension (“top-CD”) data relating to a width of the HAR structure.

Method and a system for characterising structures etched in a substrate

A method and system implementing the method for characterising structures etched in a substrate, such as a wafer, includes at least one structure etched in the substrate, an imaging step including the following steps: capturing, with an imaging device positioned on the top surface of the substrate, at least one image of a top surface of the substrate, and measuring a first data relating to the structure from at least one captured image, at least one interferometric measurement step, carried out with a low-coherence interferometer positioned on the top surface, for measuring with a measurement beam positioned on the structure, at least one depth data relating to a depth of the structure; and a first adjusting step for adjusting the measurement beam according to the first data.

Growing community of inventors

Domène, France

Wolfgang Alexander Iff