Patent attributes
A method and a structure. The structure includes: a solid core comprising a first photoresist material, the core having a bottom surface on a substrate, a top surface and opposite first and second side surfaces between the top surface and the bottom surface; and a shell comprising a second photoresist material, the shell on the top surface of the substrate, the shell containing a cavity open to the top surface of the substrate, the shell formed over the top surface and the first and second side surfaces walls of the core, the core completely filling the cavity. The core is stiffer than the shell. The method includes: forming the core from a first photoresist layer and forming the shell from a second photoresist layer applied over the core. The core may be cross-linked to increase its stiffness.