Stress control in magnetic inductor stacks
AssigneeInternational Business Machines Corporation
InventorsBruce B. Doris, Hariklia Deligianni, Eugene J. O'Sullivan, Naigang Wang
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Abstract
A magnetic laminating structure and process for preventing substrate bowing include a first magnetic layer, at least one additional magnetic layer, and a dielectric spacer disposed between the first and at least one additional magnetic layers. The magnetic layers are characterized by defined tensile strength. To balance the tensile strength of the magnetic layer, the dielectric layer is selected to provide compressive strength so as to counteract the tendency of the wafer to bow as a consequence of the tensile strength imparted by the magnetic layer(s).
Claims25
An inductor structure comprising:
- a plurality of metal lines;
- and
- a laminated film stack comprising alternating layers of magnetic materials and insulating materials enclosing the metal lines, each magnetic material layer having a tensile stress and each insulation material layer having a compressive stress, wherein the compressive stress of the insulating material layer is in an amount effective to counterbalance the tensile stress of the magnetic material layer, wherein the layers of the magnetic materials have a cumulative thickness greater than 1 micron.
A method of forming an inductor structure, comprising:
- depositing alternating magnetic and insulating layers on a processed substrate, wherein the magnetic layers have a tensile strength and the insulating layers have a compressive strength in an amount effective to counterbalance the tensile stress of the magnetic layers, wherein the magnetic layers have a cumulative thickness greater than 1 micron.
An inductor structure, comprising:
- alternating magnetic and insulating layers on a processed substrate, wherein the magnetic layers have a tensile stress and the insulating layers have a compressive stress in an amount effective to counterbalance the tensile stress of the magnetic layers, wherein each of the insulating layers has a thickness greater than each of the magnetic layers, wherein the magnetic layers have a cumulative thickness greater than 1 micron.
A closed yoke inductor, comprising:
- a laminated structure comprising alternating magnetic and insulating layers on a processed substrate, wherein the magnetic layers have a tensile strength and the insulating layers have a compressive strength in an amount effective to counterbalance the tensile stress of the magnetic layers, wherein the magnetic layers have a cumulative thickness greater than 1 micron;
- and
- a copper wire, wherein the laminated structure is wrapped around the laminated structure.
A solenoid inductor, comprising:
- a laminated structure comprising alternating magnetic and insulating layers on a processed substrate, wherein the magnetic layers have a tensile strength and the insulating layers have a compressive strength in an amount effective to counterbalance the tensile stress of the magnetic layers, wherein the magnetic layers have a cumulative thickness greater than 1 micron;
- and
- a copper wire wrapped about the laminated structure.
Dependencies are inferred from the claim text.