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Structural color fabrication attracting significant interest for science and art is usually restricted by costly and time‐consuming structuring processes or inerasable characteristics of structures. Herein, by developing a universal, low‐cost technical solution—the nanosecond laser irradiation of ink (Solvent Black 7) layers coated on metal—laser‐induced heterogeneous permanent/erasable nanostructures (LIHPEN) are produced successfully on multiple metals, especially noble metals, without ablation damage to intrinsic surfaces. LIHPEN consist of uniform laser‐induced periodic surface structures produced by surface plasmon polariton excitation of metals and can be extended into 2D hybrid micro/nanostructures by introducing the direct laser interference patterning technique. LIHPEN technology operated under a large processing parameter window can realize space‐selective erasability of prepared structures by controlling processing parameters, which determine the ink‐layer carbonization degree and thus the permanent or erasable characteristic. Because ink layers can be coated manually, in addition to realizing digital scanning patterns, LIHPEN technology can be integrated with traditional artistic techniques to solidify and color artworks without risk of information loss and leakage in digital copying. LIHPEN with good durability can exhibit vivid structural colors on metals, demonstrating its great potential in fields of artwork iridescent coloring, encryption, and anti‐counterfeiting, particularly those requiring customization, personalization, and rewritability.

The commercialization of GaN-based Schottky barrier diodes in middle- and high- voltage applications still faces many challenges, in which the lack of an effective selective area p-type doping method is one of the main obstacles. This paper proposes novel vertical GaN-based Schottky diodes with trench MIS structure and an embedded p-GaN protection layer (junction-trench MIS barrier Schottky diodes, J-TMBS). The trench structure and lateral p-n junctions can be achieved by selectively etching the very thin p-GaN and then regrowing n-GaN. Therefore, the fabrication technology avoids the selective area p-type doping process, and the dry etching damage and poor sidewall regrowth interface issue, which are serious in GaN Merged pn/Schottky (MPS) diodes, can also be alleviated for the proposed J-TMBS. Compared with the optimized GaN trench MIS barrier Schottky (TMBS) diodes, the surge current capability and dielectric reliability of the proposed J-TMBS are significantly improved (the electric field of the dielectric layer and maximum lattice temperature under the surge test can be reduced by 448% and 202%, respectively). In addition, the specific on-resistance ( R on,sp) and breakdown voltage remain basically unchanged compared with TMBS. Compared with the optimized GaN MPS diodes, the proposed structure improves the specific on-resistance by 17.2% benefiting from the reduced area of the JFET region without degrading the reverse I–V characteristics and surge current capability. The proposed J-TMBS exhibits potential in practical high voltage (>600 V) application of GaN Schottky power diodes.