Method of testing wafer
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsYen-Hsung Ho, Chia-Yi Tseng, Chih-Hsun Lin, Kun-Tsang Chuang, Yung-Lung Hsu
Life of this patent
Estimating the term…
Abstract
A method includes following steps. An image of a wafer is captured. A first contact region in the captured image at which the first conductive contact is rendered is identified. A second contact region in the captured image at which the second conductive contact is rendered is identified. The second conductive contact is determined as not shorted to the first conductive contact, in response to the identified second contact region in the captured image is darker than the identified first contact region in the captured image.
Claims20
A method, comprising:
- capturing an image of a wafer, the wafer comprising a first conductive contact over a first active region of the wafer and a second conductive contact over an oxide formed on a second active region of the wafer;
- identifying a first contact region in the captured image at which the first conductive contact is rendered;
- identifying a second contact region in the captured image at which the second conductive contact is rendered;
- and
- in response to the identified second contact region in the captured image having a brightness substantially the same as a brightness of the identified first contact region in the captured image, determining that the second conductive contact is shorted to the first conductive contact.
A method, comprising:
- capturing an image of a wafer, the wafer comprising a first conductive contact over a first doped semiconductor region and a second conductive contact over a second doped semiconductor region, wherein the first doped semiconductor region is of a first conductivity type, and the second doped semiconductor region is of a second conductivity type opposite the first conductivity type;
- identifying a first contact region in the captured image at which the first conductive contact is rendered;
- identifying a second contact region in the captured image at which the second conductive contact is rendered;
- and
- in response to the identified second contact region in the captured image having a brightness substantially the same as a brightness of the identified first contact region in the captured image, determining that the second conductive contact is shorted to the first conductive contact.
A method comprising:
- forming a first shallow trench isolation (STI) region between a first active region and a second active region of a substrate, and a second STI region between the second active region and a third active region of the substrate;
- forming a dielectric layer over the second active region;
- forming a first contact on the first active region and a second contact on the dielectric layer;
- obtaining an electron microscope image of the substrate;
- measuring a brightness difference between the first contact and the second contact rendered in the electron microscope image;
- and
- determining, based on the measured brightness difference, whether a short circuit occurs between the first contact and the second contact.
Dependencies are inferred from the claim text.