access icon free Enhanced performance of large-area vertical light-emitting diodes treated by laser irradiation

In this work, a comparative analysis of vertical light-emitting diodes (VLEDs) examining the device properties is performed with different surface treatment schemes. The VLEDs on graphite substrate are fabricated by the laser lift-off and the wafer bonding processes. The significance of KrF laser irradiation to form protrusions on the surfaces of undoped gallium nitride (u-GaN) and n-GaN is analysed in detail. The light output power of the fabricated VLEDs is significantly increased through the formation of micro-sized protrusions by the laser irradiation. For VLED irradiated with an energy density of 600 mJ/cm2 on n-GaN surface with a thin u-GaN layer, the light output power is improved by 24.8% at 350 mA without degradation of electrical properties compared with that of the conventional VLED.

Inspec keywords: wide band gap semiconductors; gallium compounds; wafer bonding; electrical conductivity; light emitting diodes; surface treatment; laser materials processing; III-V semiconductors

Other keywords: wafer bonding; current 350 mA; microsized protrusions; surface treatment; light output power; large-area vertical light-emitting diodes; graphite substrate; electrical properties; VLED; GaN; C; undoped gallium nitride; KrF laser irradiation; laser lift-off; energy density

Subjects: Light emitting diodes; Surface treatment (semiconductor technology)

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