Coil and Method of Manufacturing a Coil

A method for manufacturing a semiconductor device, the method comprising:

• forming an opening in an isolation layer, the opening comprises sidewalls and a bottom surface;
• forming a first material layer along the sidewalls of the opening in the isolation layer;
• isotropically etching the opening in the isolation layer thereby forming an extended opening lacking edges;
• removing the first material layer;
• and
• filling the extended opening with a conductive material.

A method for manufacturing a transformer, the method comprising:

• forming a first coil supported by a substrate;
• forming an isolation layer over the substrate and the first coil;
• and
• forming a second coil in the isolation layer substantially aligned with the first coil, wherein forming the second coil comprises
• forming an opening in the isolation layer;
• forming sidewall spacers along sidewalls of the opening in the isolation layer;
• isotropically etching the opening in the isolation layer thereby forming an extended opening with curved sidewalls;
• and
• depositing a conductive material in the extended opening.

A method for manufacturing an electronic device, the method comprising:

• forming an opening in an isolation layer;
• isotropically etching the opening in the isolation layer thereby forming an extended opening with curved sidewalls;
• and
• forming a conductive material in the opening.

A method for manufacturing a transformer, the method comprising:

• forming a first coil supported by a substrate;
• forming an isolation layer over the substrate and the first coil;
• and
• forming a second coil in the isolation layer substantially aligned with the first coil, wherein forming the second coil comprises
• forming an opening in the isolation layer;
• forming mechanical stable sidewall spacers along sidewalls of the opening in the isolation layer;
• cleaning the sidewall spacers such that the sidewall spacers do not cling together;
• after cleaning, isotropically etching the opening in the isolation layer thereby forming an extended opening with curved sidewalls;
• forming a conductive liner in the extended opening;
• and
• depositing a conductive material in the extended opening.