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arXiv · 2409.05003

p-(001)NiO/n-(0001)ZnO heterostructures grown by pulsed laser deposition technique

Bhabani Prasad Sahu·Amandeep Kaur·Simran Arora·Subhabrata Dhar
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Abstract

NiO/ZnO heterostructures are grown on c-sapphire substrates using pulsed laser deposition (PLD) technique. X-ray diffraction study shows that the ZnO layer epitaxially grows along [0001]-direction on (0001)sapphire surface as expected. While, the epitaxial NiO film is found to be deposited along [001]-direction on the (0001)ZnO surface. Moreover, the presence of three (001)NiO domains laterally rotated by 30° with respect to each other, has also been observed in our NiO films. The study reveals the continuous nature of the NiO film, which also possesses a very smooth surface morphology. In a sharp contrast, ZnO films are found to grow along [0001]-direction when deposited on (111)NiO layers. These films also show columnar morphology. (001)NiO/(0001)ZnO layers exhibit the rectifying current-voltage characteristics that suggests the existence of p-n junction in these devices. However, the behavior could not be observed in (0001)ZnO/(111)NiO heterojunctions. The reason could be the columnar morphology of the ZnO layer. Such a morphology can facilitate the propagation of the metal ions from the contact pads to the underlying NiO layer and suppress the p-n junction effect.

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Bhabani Prasad Sahu, Amandeep Kaur, Simran Arora, Subhabrata Dhar. 2024-09-08. p-(001)NiO/n-(0001)ZnO heterostructures grown by pulsed laser deposition technique. https://arxiv.org/abs/2409.05003

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