Fig. 2: Dome fabrication techniques.

a Side view schematic of a 2D material sitting on top of a pre-patterned nanocavity with circular base footprint (R). b Pressure bulging method where monolayer 2D material membranes are deposited over etched holes. Gas (N₂, Argon or Air) is inserted into the test chamber and a pressure is applied on the bottom surface of the membrane, generating a dome. Dome height (h_m) can be manipulated via the applied pressure on the bottom surface. In (a) and (b), the 2D material thickness to substrate is not to scale. c Schematic illustration of graphene domes induced by an AFM tip (top). Outward radial pattern of domes created by an AFM tip at different tip voltages⁷⁴. d Schematic diagram of a water droplet-assisted transfer process forming spontaneous blisters. The process is listed in 6 steps, whereby contaminants are trapped underneath a 2D material resulting in domes⁷⁷. e Dome inflating/deflating process. i) Optical microscopy image of a proton irradiated (d_H = 8 × 10¹⁶ protons/cm⁻²) WS₂ sample at T = 300 K. ii) Same as (i) at T = 4 K, resulting in no dome formations. iii) Histogram of the transition temperature at which domes appear⁸¹. f Schematic formation of domes due to impinging protons penetrating 2D material basal layers⁸¹. g Proton irradiated MoS₂ dome engineering using an 80 nm thick mask with opening size (S) when i) S = 3 μm, and ii) S = 1 μm. The diameter of the domes in this case is determined by S and engineered modulation of aspect ratios (h_m/R) is possible⁸². Figure d adapted from Copyright (2022) Wiley. Used with permission from (Wang. W. et al., Mechanical Behaviour of Blisters Spontaneously Formed by Multilayer 2D Materials, Advanced Materials). Figures e and f adapted from Copyright (2019) Wiley. Used with permission from (Tedeschi. D. et al., Controlled Micro/Nanodome Formation in Proton-Irradiated Bulk Transition-Metal Dichalcogenides, Advanced Materials). Figure g adapted from Copyright (2020) Wiley. Used with permission from (Blundo. E. et al., Engineered Creation of Periodic Giant, Nonuniform Strains in MoS₂ Monolayers, Advanced Materials Interfaces).