Ga2O3 Substrate with Chamfered Edge for Crack Resistance

The patent applies local quality by creating a chamfered region at the outer periphery of the substrate that has different structural characteristics from the central portion. This chamfered region with reduced thickness and modified geometry locally absorbs stress concentrations, while the central portion maintains the uniform crystal structure needed for device fabrication. This resolves the contradiction by providing crack resistance at critical locations without compromising overall crystal growth quality.

The patent implements preliminary action by pre-forming the chamfered region during crystal growth or subsequent processing before the substrate is subjected to stress or device fabrication. This preemptive structural modification eliminates potential crack initiation sites at the outer periphery, allowing the substrate to maintain strength during handling and processing while preserving the cleavability needed for crystal growth.

The patent applies local quality by dividing the substrate into distinct regions: a central portion with uniform crystal structure and hardness suitable for device fabrication, and an outer peripheral chamfered region with modified geometry. This regional differentiation allows the large-diameter substrate to maintain hardness uniformity in the central area where devices are manufactured, while the outer region accommodates the size increase without compromising overall quality.

The patent segments the substrate into functionally distinct zones: the central portion for active device fabrication and the outer peripheral chamfered region for stress relief and handling. This segmentation allows each region to be optimized independently, enabling large-diameter substrates to maintain hardness uniformity in the central area while the outer region provides structural support and crack resistance.

The patent applies local quality by creating the chamfered region with specific geometric characteristics that enhance cracking resistance through stress distribution, rather than increasing hardness throughout the entire substrate. This localized structural modification achieves the desired strength improvement without introducing crystal defects across the whole substrate, preserving the uniform composition needed for high-quality device fabrication.

The patent implements preliminary action by pre-forming the chamfered region with optimized geometry that provides crack resistance before device fabrication. This preemptive structural design achieves the required hardness and strength characteristics without needing to increase overall crystal defect concentration, as the chamfered geometry itself provides the mechanical advantage for crack resistance.