Methods for wafer-to-wafer bonding

A method comprising:

• patterning a p-type layer of a semiconductor material to form, along a first surface of the p-type layer, a plurality of alternating high resistivity areas and low resistivity areas, wherein the low resistivity areas correspond to light emitters that have not yet been singulated into separate light emitting diodes, and wherein the high resistivity areas correspond to portions of the p-type layer that have a higher resistivity than the low resistivity areas;
• bonding a base wafer to the first surface of the p-type layer after the plurality of alternating high resistivity areas and low resistivity areas have been formed, wherein the base wafer is bonded to the first surface of the p-type layer:
• (i) after planarizing the first surface of the p-type layer, after depositing a bonding layer on the first surface of the p-type layer, and after depositing a contact layer on the first surface of the p-type layer or (ii) via a metal layer and an oxide layer;
• removing a substrate from a second surface of the semiconductor material, wherein the second surface of the semiconductor material is opposite to the first surface of the p-type layer;
• and
• patterning a trench between each adjacent pair of the light emitters, wherein the patterning singulates the light emitters.