Novel Fabrication Of Electroplated 3D Micro-Coils Using 3D Photolithography Of Thick Photoresist

We have developed a novel and high-yield process to fabricate electroplated 3D micro-coils. In our novel concept as shown in Figure 1, we decompose the 3D micro-coil, which is solenoid-type integrated inductor in other words, into two parts, the bottom conductor lines and the air bridges, and form the single-body air bridges during only one electroplating step. This does not mean the air bridges are made by the conventional way, which stacks layers of posts (or vias) and upper conductor lines vertically, and hence is a complex and low-yield process.