公开(公告)号：US20220007958A1

公开(公告)日：2022-01-13

申请号：US17295318

申请日：2019-11-29

Applicant: Northwestern University

Inventor： Matthew Allen Grayson ,  Chulin Wang ,  Claire Cecelia Onsager ,  Can Cenap Aygen ,  Charles M. Costakis ,  Lauren E. Lang ,  Andreas Tzavelis ,  John Ashley Rogers

IPC: A61B5/0536

Abstract: The disclosed 2-D and 3-D tomographic resistance imaging method improves tomographic resistance image resolution by adopting an orthogonal basis with the maximum number of elements N to describe the maximum resolution resistivity map ρ(r), where this number of elements N is set according to the number of electrodes Q; by defining the orthogonal basis according to any known constraints in the problem, thereby enhancing the resolution where it is needed; by positioning electrodes to be sensitive to these basis functions; and by choosing current I and voltage V contact electrode pairs that maximize signal-to-noise ratio.

公开(公告)号：US20230395112A1

公开(公告)日：2023-12-07

申请号：US18327725

申请日：2023-06-01

Applicant: Northwestern University

Inventor： Matthew A. Grayson ,  Pedram Khalili-Amiri ,  Chulin Wang ,  Claire Cecelia Onsager ,  Sevde Nur Arpaci ,  Victor Lopez Dominguez

IPC: G11C11/15 ,  G11C11/16 ,  G11B5/31

CPC classification number: G11C11/15 ,  G11B5/3116 ,  G11B5/3169 ,  G11C11/161

Abstract: According to certain aspects of the present disclosure, a device is provided. The device includes a thin film of cobalt. A platinum layer is disposed on the thin film of cobalt. An aluminum layer is disposed on the platinum layer. The aluminum layer disposed on the platinum layer encapsulates the thin film of cobalt. A plurality of electrical contacts is in electrical communication with the thin film of cobalt. Two electrical contacts of the plurality of electrical contacts are configured to receive a write-current therebetween. Four electrical contacts of the plurality of contacts are configured for reading a 4-point resistance.

公开(公告)号：US20230081541A1

公开(公告)日：2023-03-16

申请号：US18049551

申请日：2022-10-25

Applicant: Northwestern University

Inventor： Matthew Allen Grayson ,  Chulin Wang ,  Claire Cecelia Onsager ,  Can Cenap Aygen ,  Charles M. Costakis ,  Lauren E. Lang ,  Andreas Tzavelis ,  John Ashley Rogers ,  Suzan van der Lee

IPC: A61B5/0536 ,  G06T11/00

Abstract: The disclosed 2-D resistance tomographic imaging method optimizes computation speed for performing electrical impedance tomography using a model-space with a minimal number of orthonormal polynomial basis functions to describe discernable features in the 2-D resistance tomographic image, determining a minimal number of contacts to take fewer measurements than available information based on the number of basis functions, selecting a subset of rows of a matrix of calculated sensitivity coefficients to form a square Jacobian matrix for a linearized forward problem to be solved and inversion of the linear forward problem, and solving an inverse problem based on the square Jacobian matrix by performing at least one iteration of a Newton's method solve.

公开(公告)号：US11525847B2

公开(公告)日：2022-12-13

申请号：US17484939

申请日：2021-09-24

Applicant: NORTHWESTERN UNIVERSITY

Inventor： Matthew Grayson ,  Chulin Wang ,  Juncen Li ,  William H. Reinhardt

IPC: G01R19/00 ,  G01R33/07 ,  H01L35/28

Abstract: Systems and methods include an electrical switch that establishes a first electrical conducting path between terminals of an electrical measurement apparatus through one or more electrical leads and an electrically-conductive sample in a first state, and a second electrical conducting path between the terminals through the one or more electrical leads while bypassing the sample in a second state. A voltage VS+L is measured across all of the sample and the one or more electrical leads in the first state, while a voltage VL is measured across the one or more electrical leads while bypassing the sample in the second state. Calculations according to the equation VS=VS+L−VL are performed to determine a precision DC voltage measurement of a voltage across the sample VS in the absence of Seebeck voltage offsets contributed by the one or more electrical leads.

公开(公告)号：US20220099711A1

公开(公告)日：2022-03-31

申请号：US17484939

申请日：2021-09-24

Applicant: NORTHWESTERN UNIVERSITY

Inventor： Matthew Grayson ,  Chulin Wang ,  Juncen Li ,  William H. Reinhardt

IPC: G01R19/00 ,  H01L35/28 ,  G01R33/07

Abstract: Systems and methods include an electrical switch that establishes a first electrical conducting path between terminals of an electrical measurement apparatus through one or more electrical leads and an electrically-conductive sample in a first state, and a second electrical conducting path between the terminals through the one or more electrical leads while bypassing the sample in a second state. A voltage VS+L is measured across all of the sample and the one or more electrical leads in the first state, while a voltage VL is measured across the one or more electrical leads while bypassing the sample in the second state. Calculations according to the equation VS=VS+L−VL are performed to determine a precision DC voltage measurement of a voltage across the sample VS in the absence of Seebeck voltage offsets contributed by the one or more electrical leads.