Method of fabricating a coplanar waveguide device including removal of spurious microwave modes via flip-chip crossover

Patent metadata

Field	Value
Publication number	US-9455392-B2
Application number	US-201514610551-A
Country	US
Kind code	B2
Filing date	Jan 30, 2015
Priority date	Mar 15, 2013
Publication date	Sep 27, 2016
Grant date	Sep 27, 2016

Abstract

A coplanar waveguide device includes a coplanar waveguide structure disposed on a substrate, at least one qubit coupled to the coplanar waveguide structure and an add-on chip having a metallized trench, and disposed over the substrate.

First claim

What is claimed is:

1. A method of fabricating a coplanar waveguide (CPW) device, the method comprising:
fabricating a qubit circuit chip;
wherein fabricating the qubit circuit chip comprises:
patterning a CPW structure;
fabricating at least one qubit; and
coupling the at least one qubit to the CPW structure;

fabricating an add-on chip configured to remove spurious microwave modes from the qubit circuit chip;
wherein fabricating the add-on chip comprises:
defining a trench in a substrate, the trench matching an outline of the at least one qubit, wherein the trench comprises an opening; and
metalizing the trench and the substrate;

disposing the add-on chip on the qubit circuit chip such that the opening in the trench faces the qubit circuit chip; and
wherein the patterning of the CPW structure comprises forming ground planes on the qubit circuit chip and wherein the ground planes are exposed by the opening.

2. The method of claim 1 , wherein the trench and substrate are metallized with niobium (Nb).

3. The method of claim 1 , wherein patterning the CPW structure further comprises:
forming a resonator;
forming a drive pad coupled to the resonator; and
forming a qubit pocket coupled to the resonator.

Assignees

• IBM

Inventors

• Abraham David W
• Chow Jerry M
• Corcoles Gonzalez Antonio D
• Keefe George A
• Rothwell Mary E
• Rozen James R
• Steffen Matthias

Classifications

• H01L39/2406 Primary

  Electricity · mapped topic

• H01P11/003

  Manufacturing lines with conductors on a substrate, e.g. strip lines, slot lines · CPC title

• B82Y10/00

  Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic · CPC title

• H01P3/026

  Coplanar striplines [CPS] · CPC title

• H01P3/003

  Coplanar lines · CPC title