A non-volatile method with a self-aligned RRAM element. The method includes a lower electrode element, generally planar in form, having an inner contact surface. At the top of the device is a upper electrode element, spaced from the lower electrode element. A containment structure extends between the upper electrode element and the lower electrode element, and this element includes a sidewall spacer element having an inner surface defining a generally funnel-shaped central cavity, terminating at a terminal edge to define a central aperture; and a spandrel element positioned between the sidewall spacer element and the lower electrode, having an inner surface defining a thermal isolation cell, the spandrel inner walls being spaced radially outward from the sidewall spacer terminal edge, such that the sidewall spacer terminal edge projects radially inward from the spandrel element inner surface. ARRAM element extends between the lower electrode element and the upper electrode, occupying at least a portion of the sidewall spacer element central cavity and projecting from the sidewall spacer terminal edge toward and making contact with the lower electrode. In this manner, the spandrel element inner surface is spaced from the RRAM element to define a thermal isolation cell adjacent the RRAM element.