# Creation of One- and Two-Dimensional Copper and Zinc Oxides Semiconductor Structures
## 2 Formation of One- and Two-Dimensional ZnO and CuO Structures
Liquid-phase routes, including sol-gel-assisted dip-and-spin coating, spray pyrolysis, and electrodeposition, are also used [93]. To create thin films and two-dimensional CuO layers, besides chemical bath deposition (CBD) [94; 95; 96], atomic layer deposition (ALD) [97; 98] is used. One of the methods for synthesizing one-dimensional and two-dimensional structures of zinc oxide (ZnO) and copper oxide (CuO) is thermal oxidation [99]. This method is based on the controlled oxidative transformation of corresponding metallic precursors at high temperatures in an oxygen or air atmosphere. The thermal oxidation process can be utilized to create nanostructures with different shapes and sizes, making it an important tool in the field of nanotechnology and nanomaterials [100; 101]. Thermal treatment is a relatively simple and cost-effective technique that does not require expensive equipment. This method can be easily scaled up for the synthesis of large quantities of material, making it attractive for industrial applications [102]. One of the drawbacks of this method is the complexity of process control. Achieving the desired material properties and structure requires careful control of synthesis parameters such as the temperature, processing time, and gas environment. Additionally, thermal treatment typically involves high temperatures, which may limit its applicability for thermally sensitive materials or certain types of substrates [103]. Laser-based methods are also used for the synthesis of one-dimensional, quasi-one-dimensional, and two-dimensional structures of both zinc oxide (ZnO) and copper oxide (CuO) materials. 1D ZnO structures are fabricated by pulsed laser ablation (PLA), which involves using a high-energy laser to ablate a ZnO target, resulting in the formation  
Figure 4: Two-step process of the fabrication of ZnO nanorods, which contains the sol–gel process and subsequent hydrothermal synthesis [70]. of ZnO nanowires or nanorods [104; 105]. The method of pulsed laser ablation can be applied to synthesize two-dimensional porous ZnO nanosheets and their hybrids with one-dimensional carbon nanotubes [106]. The SEM image of this kind of hybrid material is presented in Figure 5.  
Laser-assisted chemical bath deposition (LA-CBD) is also an efficient method for growing 1D ZnO nanostructures due to its high productivity. In [107], it was shown that, at least for the used parameter range of the continuous-wave (CW) laser, with increasing power of the laser beam during bath deposition, the growth of ZnO nanostructures was enhanced, resulting in improved morphology and electrical conductivity. Laser-ablation synthesis in solution (LASiS), which combines laser ablation with solution chemistry, was used to produce one-dimensional CuO nanowires or nanorods, as well as CuO thin films [108]. Post-ablative laser irradiation of nanomaterials in suspension states was used for additional modification of their geometry: Size and shape [109]. The laser-induced hydrothermal growth (LIHG) [110], which can be realized using continuous laser sources, also seems to be promising. Laser-assisted chemical vapor deposition (CVD) combines laser irradiation with chemical vapor deposition to grow ZnO and CuO thin films. In [111], it was shown that the average grain size was increased with increasing laser irradiation power density, which, however, at large levels may have resulted in the formation of discontinuous precipitates with large voids. When pulsed laser deposition (PLD) is used to fabricate two-dimensional copper oxide structures, a high-energy laser is used to ablate a copper target, creating a plume of copper atoms. These atoms then condense on a substrate and form thin CuO films, which by their nature can be two-dimensional [112]. Pulsed laser deposition (PLD) can be used to synthesize vertically oriented zinc oxide nanowires [113], as well as to deposit thin films and 2D layers of ZnO on substrates, allowing for precise control over film thickness and properties [114; 115].