Abstract: An integrated circuit test structure is comprised of a stacked substrate MLC space transformer (5). A top surface of an interface substrate (12) is employed for decoupling capacitor (36) placement. The top surface has metal conductors (20) exposed thereon for terminating power supply buses from a tester (1). Individual layers of a personalization substrate (14) are fabricated to redundantly extend internal power plane metalization (22) to the sidewalls. Redundant pads (26) are placed on each personalization layer to increase the surface area for side mount contact. Metal pads (18) are deposited over the exposed sidewall metal for forming a sidewall contact to the power planes within the personalization substrate.