A fine pitch solder bump structure with a built-in stress buffer that is utilized in electronic packages, and a method of producing the fine pitch solder bump structure with built-in stress buffer. Employed is a very thick final passivation layer that is constituted of a polyimide as a so-called “cushion” for a minimal thickness of UBM (BLM) pad and solder material, while concurrently completely separating the resultingly produced polyimide islands, so that the polyimide material provides most of the physical height for the “standoff” of a modified C4 (controlled collapse chip connection) structure. In employing the polyimide material as the primary structural component of the vertical chip package interconnect in this particular inventive manner, the inherent stress buffering property of the polyimide material is utilized to full advantage by effectively reducing the high stresses encountered during chip manufacture processing steps, such as chip join, reflow, preconditioning and reliability thermal cycle stressing.