Fabrication of an integrated transformer

A method for forming an integrated transformer within a semiconductor layer stack of a semiconductor substrate, the method comprising:

• forming a plurality of bottom conductors along a first horizontal direction within a first layer of the semiconductor layer stack to form a first portion of a primary winding of the integrated transformer to provide a primary path for a first electronic circuit;
• depositing and patterning one or more magnetic or ferromagnetic materials along a second horizontal direction, orthogonal to the first horizontal direction, within a second layer of the semiconductor layer stack that is over the plurality of bottom conductors to form a magnetic core of the integrated transformer that is orthogonal to the plurality of bottom conductors;
• forming a plurality of top conductors along the first horizontal direction within a third layer of the semiconductor layer stack to form a second portion of the primary winding that is parallel with the first portion of the primary winding to provide a reverse path for the first electronic circuit, the plurality of top conductors being formed to be laterally displaced from the plurality of bottom conductors such that the plurality of top conductors and the plurality of bottom conductors do not overlap each other in a vertical direction passing through the magnetic core;
• and
• forming a coupling element within the first layer, the second layer, and the third layer of the semiconductor layer stack to wrap around the magnetic core to form a secondary winding of the integrated transformer, the coupling element including a first connection within the first layer of the semiconductor layer stack and a second connection within the second layer of the semiconductor layer stack to electrically connect the secondary winding of the integrated transformer to a second electronic circuit.

A method for forming an integrated transformer, the method comprising:

• forming a plurality of bottom conductors along a first horizontal direction within a first layer of a semiconductor layer stack to form a first portion of a primary winding of the integrated transformer to provide a primary path for a first electronic circuit;
• depositing and patterning one or more magnetic or ferromagnetic materials that are over the plurality of bottom conductors within a second layer of the semiconductor layer stack that is beneath the first layer of the semiconductor layer stack to form a magnetic core of the integrated transformer along a second horizontal direction that is orthogonal to the first horizontal direction;
• forming a plurality of top conductors along the first horizontal direction within a third layer of the semiconductor layer stack that is beneath the second layer of the semiconductor layer stack to form a second portion of the primary winding that is parallel with the first portion of the primary winding to provide a reverse path for a first electronic circuit, the plurality of top conductors being formed to be laterally displaced from the plurality of bottom conductors such that the plurality of top conductors and the plurality of bottom conductors do not overlap each other in a vertical direction passing through the magnetic core;
• and
• forming a coupling element within the first layer, the second layer, and the third layer of the semiconductor layer stack to wrap around the magnetic core to form a secondary winding of the integrated transformer, the coupling element including a first connection within the first layer of the semiconductor layer stack and a second connection within the second layer of the semiconductor layer stack to electrically connect the secondary winding of the integrated transformer to a second electronic circuit.