Method of forming superconductor structures

A method of forming a superconductor structure, the method comprising:

• forming a first opening in a first dielectric layer overlying a substrate;
• performing a wet etch to remove oxides from the first dielectric layer caused by the forming of the first opening;
• forming a first superconductive line in the first opening having a top surface aligned with a top surface of the first dielectric layer;
• performing a first cleaning process on the top surface of the first superconductive line and the top surface of the first dielectric layer to remove oxides from the top surface of the first superconductive line and the top surface of the first dielectric layer;
• forming a second dielectric layer over the first dielectric layer and the first superconductive line;
• forming a via opening in the second dielectric layer to a top surface of the superconductive line, and a trench opening surrounding the via opening and partially extending into the second dielectric layer;
• performing a second cleaning process on the top surface of the first superconductive line to remove oxides formed on the top surface of the first superconductive line and the remaining portions of the superconductor structure;
• forming a protective barrier over the top surface of the first superconductive line at a first processing stage to mitigate oxide formation over the top surface of the superconductive line;
• moving the superconductor structure to a second processing stage for further processing;
• removing the protective barrier;
• forming a contact in the via opening and a second conductive line in the trench opening.

A method of forming a superconductor interconnect structure, the method comprising:

• forming a first dielectric layer overlying a substrate
• forming a patterned photoresist layer with an opening overlying the first dielectric layer;
• etching the first dielectric layer to form an extended opening in the first dielectric layer based on the opening in the photoresist layer;
• stripping the photoresist layer;
• performing a wet etch to remove the oxide layer on the first dielectric layer caused by the stripping of the photoresist layer;
• performing a contact material fill to fill the extended opening and form a first superconductive line;
• performing a chemical mechanical polish (CMP) to align a top surface of the first superconductive line with a top surface of the first dielectric layer;
• performing a first cleaning process on the top surface of the first superconductive line and the first dielectric layer to remove oxides formed on the top surface of the first superconductive line and the top surface of the first dielectric layer;
• forming a second dielectric layer over the first dielectric layer and the first superconductive line;
• forming a via opening in the second dielectric layer to a top surface of the first superconductive line, and a trench opening surrounding the via opening and partially extended into the second dielectric layer;
• performing a second cleaning process on the top surface of the first superconductive line to remove oxides formed on the top surface of the first superconductive line during the forming of the via opening and trench opening;
• forming a first protective barrier over the top surface of the superconducting element;
• moving the superconductor structure to a subsequent stage for further processing;
• performing an argon sputter clean to remove the protective barrier;
• performing a superconducting contact material fill to fill the via opening and the trench opening to form a contact in the via opening and a second superconductive line in the trench opening;
• performing a chemical mechanical polish (CMP) to align a top surface of the second superconductive line with a top surface of the second dielectric layer;
• performing a third cleaning process to remove oxides formed on a top surface of the second dielectric layer and the top surface of the second superconductive line;
• and
• forming a second protective barrier on the top surface of the second superconductive line to protect the second superconductive line from further oxidization when being moved to a subsequent stage for further processing.