A hard disk drive flexure assembly includes a base layer, a conductive layer, a plurality of electrical pads over the conductive layer, and a sidewall layer including sidewalls on each side of and extending higher than a corresponding electrical pad. Pre-solder bumps are formed between the sidewalls and over each pad. Use of sidewalls prevents the pre-solder bumps from undesirably bridging to an adjacent electrical pad and forming a short circuit, which might otherwise cause head-gimbal assembly (HGA) manufacturing failures and consequent increased cost. These techniques are especially relevant with narrow, high-density, small pitch electrical pads.