Hitachi-High-Technologies Corporation

Hitachi High-Tech Corporation

Takanori Kondo

Toshifumi Honda

Takahiro Jingu

Masaaki Ito

Nobuhiro Obara

Akira Hamamatsu

Masami Makuuchi

Takahiro Urano

Masami Ikota

Hideo Ota

Yoshio Kimoto

Provided is a defect inspection apparatus including a plurality of detection optical systems for collecting illumination scattered light from the surface of a sample, a plurality of sensors for converting the illumination scattered light collected by the corresponding detection optical systems into electrical signals and outputting detection signals, and a signal processing device for processing the detection signals input from the plurality of sensors, wherein the signal processing device generates a first signal group including an integrated signal obtained by adding a plurality of detection signals in a predetermined combination based on a group of detection signals input from the plurality of sensors, generates a second signal group by performing the filtering processing on each signal that configures the first signal group, generates a third signal group including separated signals separated according to a predetermined rule from the signal corresponding to the integrated signal based on the second signal group, and detects or classifies defects based on the third signal group to store defect inspection data in a memory.

Defect inspection apparatus and defect inspection method

The present disclosure proposes a method for classifying defects and the like by using a learning device that has been suitably trained, a system, and a computer-readable medium. As one aspect thereof, the present disclosure proposes (see FIG.) a defect inspection method, etc., in which one or more computers are used to inspect a defect on a sample on the basis of output information from detectors that detect scattered light produced via the irradiation of the sample with light, wherein defect information is outputted by: receiving output from a plurality of detectors disposed at a plurality of angles of elevation with reference to the sample surface, and at a plurality of sample surface-direction orientations with reference to the irradiation points of the light on the sample; and inputting the output information of the plurality of detectors into a learning device that has been trained using the output information from the plurality of detectors and the defect information.

Method for defect inspection, system, and computer-readable medium

In order to prevent an erroneous determination of an on-film defect, the sensitivity of the post-inspection is reduced so that a film swelling due to a minute defect would not be detected. Classification is performed to determine whether a defect is at least one of an on-film defect and a film swelling, by performing a coordinate correction on the result of a post-inspection by an actual-defect fine alignment using the result of a pre-inspection performed with two-stage thresholds, and by checking defects against each other. In addition, classification is performed to determine whether a defect is at least one of an on-film defect and a film swelling by, during the post-inspection, preparing instruction data from information of the refractive index and thickness of a film formed on a wafer and comparing the instruction data with a signal intensity ratio of a detection system.

Defect classification device, inspection device, and inspection system

The invention discloses a technique that estimates micro roughness from a total sum of detection signals from plural detection systems and signal ratios, using a light scattering method. The technique rotates and translates a wafer at high speed to measure the entire surface of the wafer with high throughput. The relationship between the micro roughness and the intensity of scattered light varies according to a material of the wafer and a film thickness thereof. Moreover, calibration of an apparatus is also necessary. Thus, for instance, the invention provides a technique that has a function of correcting an optically acquired detection result using a sample which is substantially the same as a measurement target and makes the optically acquired detection result come close to a result measured by an apparatus, such as an AFM, using a different measurement principle.

Surface measurement apparatus

In conventional technologies in surface measurement and defect inspection, considerations are not made for the following points: (1) coarseness of resolution of spatial frequency; (2) variation of detection signal resulting from anisotropy of microroughness; and (3) variation of background signal resulting from anisotropy of microroughness. The present invention is characterized by acquiring a feature quantity about the anisotropy of the microroughness of the substrate surface. Further, the present invention is characterized by acquiring a surface state in consideration of the anisotropy of the microroughness of the substrate surface. Further the present invention is characterized by detecting a defect over the substrate in consideration of the anisotropy of the microroughness of the substrate surface.

Growing community of inventors

Tokyo, Japan

Takanori Kondo