Position-controlled remote epitaxy of ZnO for mass-transfer of as-deployed semiconductor microarrays

Abstract

We report the site-selective remote epitaxial growth of mechanically transferable ZnO microrod (MR) and microdisk (MD) arrays via hydrothermal growth. To designate the growth sites, a hole-patterned poly(methyl methacrylate) mask layer is formed on the graphene-coated GaN substrate. ZnO microarrays are exclusively grown to be either MR or MD on graphene-exposed patterned areas via the remote epitaxy. The remote heteroepitaxial relation between ZnO and GaN across graphene is observed by atomic resolution scanning transmission electron microscopy. The non-covalent remote epitaxial interface allows the mechanical lift-off of the ZnO microarrays and mass-transfer onto a surface of interest using a sticky tape as those arrays are well maintained. The donor substrate is refurbished for repetitive position-controlled remote epitaxy. This study provides a simple method of fabricating mass-transferable microarrays of semiconductors that can maintain the addressable spatial arrays of semiconductors to an arbitrary receiver substrate for ease of heterogeneous integration without an additional assembly process for position control.

Long-Range Orbital Hybridization in Remote Epitaxy: The Nucleation Mechanism of GaN on Different Substrates via Single-Layer Graphene

“…Therefore, remote epitaxy is the most promising technology for obtaining high-quality single-crystal films. More importantly, remote epitaxy has more advantages in device fabrication, such as flexible device transfer, recycling of the substrate, and good luminescence characteristics. − The heterogeneous interface between 2D and 3D materials is important for the realization of remote epitaxy. GaN substrate decomposition at high temperatures will disrupt the structure of graphene, thus not enabling the exfoliation of the epilayer from the substrate .…”

Exceptional Thermochemical Stability of Graphene on N-Polar GaN for Remote Epitaxy

“…Remote epitaxy represents an innovative growth method that dictates the epitaxial relation across the ultrathin, lattice-transparent two-dimensional (2D) layer, thereby facilitating epi-layer separation without inflicting damage by laser-assisted melting or chemical etching. Given the van der Waals (vdW) surface of standard 2D materials, the weakly bound epitaxial interface allows easy separation of the epi-layer through techniques such as sticky tape- or metal stressor-assisted exfoliation. ,− Moreover, the weak vdW interface releases strain caused by lattice mismatch, resulting in an epi-layer with fewer crystal defects. , In addition, the robust 2D layer shields the underlying substrate from contamination, damage, and unwanted chemical reaction during the remote epitaxy process, allowing for reuse of the wafer over again. , The remote epitaxy has been applied to fabricate heterogeneously integrated three-dimensional (3D) multifunctional devices with high density by stacking the released epi-layer membrane and implementing standard microelectronic processes (e.g., photolithography, metallization) . Accordingly, remote epitaxy could be promising for overcoming the limitations of direct-bonded epitaxy, including substrate damage, limited material choices for matching crystal parameters, damage from laser/chemical lift-off, and so on.…”

Characteristics of flexible ZnO nanorod UV photodetectors processed by using a direct silicon etching transfer method

“…In particular, LLO, which is typically employed in the electronic industry, is the process of separating a prefabricated device from the original substrate using an excimer laser beam. [13][14][15][16] However, the devices separated by using the LLO process exhibit significantly degraded properties owing to stress-and heat-induced damage caused by the laser. [17][18][19] By contrast, in a CLO process, a sacrificial layer is chemically etched to separate the device from the original substrate, and CLO has been studied as an alternative to LLO because it involves relatively less heat and stress.…”