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Wafer-to-wafer bonding is being used to extend Moore's law and enable heterogenous integration. However, traditional bonding dielectrics for wafer bonding such as SiCN or <tex>$\text{SiO}_{2}$</tex> have low thermal conductivities (<tex>$\mathrm{k}<1.4 \mathrm{W} / \text{mK}$</tex>) which results in heat trapping at the bonding interface and degraded device performance. To increase heat dissipation, Aluminum Nitride (AlN) is proposed as a new bonding dielectric due to its higher thermal conductivity, electrically insulating properties, and BEOL compatible deposition temperature (<tex>$<400{ }^{\circ} \mathrm{C}$</tex>). AlN films were deposited by PVD with thicknesses from <tex>$30-250 \text{nm}$</tex> and were tested for thermal conductivity and wafer bonding criteria. From this development void-free direct bonding of 30 nm AlN films was established using a surface activation plasma; however, the bonding energy was too low for downstream processing (<tex>$<1.2$</tex> <tex>$\mathrm{J} / \mathrm{m}^{2}$</tex>). To improve the bond quality, a thin <tex>$<5 \text{nm}$</tex> ALD <tex>$\text{Al}_{2} \mathrm{O}_{3}$</tex> capping layer is deposited on top of the AlN film. This film increased bonding energy to <tex>$2.75 \mathrm{J} / \mathrm{m}^{2}$</tex> without impacting the thermal properties of the bonding films stack. The <tex>$\text{AlN}+\text{Al}_{2} \mathrm{O}_{3}$</tex> film stack was shown to increase the effective thermal conductivity across a bonding interface by up to 36% which highlights its ability to dissipate hot spots in ILD layers. Finally, we study the impact of AlN on Post-Bond Litho Overlay (PBLO) for potential integration in BSPDN process flows where reducing bonding distortion is crucial.