Patent ID: 6677659
Filing Date: 2004-01-13
Classification: H01L

Abstract:
A method for fabricating a 3-dimensional solenoid comprising the steps of:providing a pre-processed semiconductor substrate; depositing a first silicon dioxide layer on a top surface of said substrate; depositing a layer of a first metal on said first silicon dioxide layer; patterning said first metal layer into an inductor coil having a first end at near the center and a second end at an outer periphery of said inductor coil; depositing a second silicon dioxide layer on top of said inductor coil and said first silicon dioxide layer; patterning via openings in said second silicon dioxide layer exposing said first end and said second end of said inductor coil; filling said via openings with a second metal forming two vias over said first end and said second end of the inductor coil, respectively; depositing a third silicon dioxide layer over said two vias and said second silicon dioxide layer; patterning first trench openings f or suspended arms in said third silicon dioxide layer with inner ends of said first trench openings exposing said two vias; depositing a layer of said first metal into said trenches forming two suspended arms; depositing a fourth silicon dioxide layer over said two suspended arms and said third silicon dioxide layer; patterning second trench openings on and exposing said two suspended arms; depositing a third metal in said second trench openings, said third metal having a coefficient of thermal expansion smaller than that for said first metal forming bi-layered suspended arms; and removing said first, second, third and fourth silicon dioxide layers from said top surface of the substrate and exposing said inductor coil, said vias and said bi-layered suspended arms.