A curved spring structure includes a base section extending parallel to
the substrate surface, a curved cantilever section bent away from the
substrate surface, and an elongated section extending from the base
section along the substrate surface under the cantilevered section. The
spring structure includes a spring finger formed from a self-bending
material film (e.g., stress-engineered metal, bimorph/bimetallic) that is
patterned and released. A cladding layer is then electroplated and/or
electroless plated onto the spring finger for strength. The elongated
section is formed from plating material deposited simultaneously with
cladding layers. To promote the formation of the elongated section, a
cementation layer is provided under the spring finger to facilitate
electroplating, or the substrate surface is pre-treated to facilitate
electroless plating.