Direct bonding methods and structures for dies

An apparatus, comprising:

• a substrate having a first bonding surface;
• and
• a die, wherein the die comprises:
• a second bonding surface on a first side of the die, wherein the second bonding surface is directly bonded to the first bonding surface;
• and
• a backside dielectric layer that forms a second side of the die, wherein the second side of the die is opposite the first side of the die and wherein the backside dielectric layer comprises an unpatterned dielectric layer.

A method of forming a microelectronic device, comprising:

• providing a first substrate having a first surface;
• determining a bow of the first substrate;
• determining a thickness of a stress balancing layer to be formed based in part on the measured bow;
• thinning the first substrate to form a thinned substrate, wherein the thinned substrate comprises the first surface and second surface and wherein the first and second surfaces are on opposing sides of the thinned substrate;
• forming the stress balancing layer onto the second surface such that the stress balancing layer has the determined thickness;
• after forming the stress balancing layer onto the second surface, singulating the thinned substrate into a plurality of dies;
• and
• direct bonding at least one of the plurality of dies to a second substrate.