Atomic-scale precision lossless layer-by-layer etching method for two-dimensional layered material

[0047] This example introduces a non-destructive layer-by-layer etching method with atomic-level precision for two-dimensional layered materials.

[0048] The difficulty of the present invention is to realize the following two points simultaneously in material etching processing:

[0049] 1) Obtain high-precision etching at the single-atom level;

[0050] 2) Obtain an ultra-high etching selectivity ratio, so that the etching medium can effectively remove the etching layer without damaging the material retention layer and maintain its intrinsic physical properties.

[0051] Please refer to figure 1 , figure 1 A flow chart of an atomic-level precision non-destructive layer-by-layer etching method for a two-dimensional layered material provided by the present invention, which shows a two-dimensional layered material atomic-level precision non-destructive layer-by-layer etching method, including the following steps :

[0052] Please refer to figure 2 , figure 2 A schematic...

[0068] Based on the above-mentioned embodiment 1, this embodiment introduces in detail a non-destructive layer-by-layer etching method with atomic-level precision for a two-dimensional layered material.

[0069] Step 1: Use the mechanical stripping method to remove the MoS to be etched 2 The nanosheets are transferred to silicon wafers.

[0070] Step 2: Spin-coat PMMA electron beam glue, and define the area to be etched by electron beam exposure.

[0071] Step 3: Pattern the MoS to be etched 2 The nanosheets were placed in reactive ion etching (RIE), and were bombarded with plasma for 30s at low power (30W) to introduce lattice defects on the surface of the area to be etched.

[0072] Step 4: On the MoS to be etched 2 10nm metallic aluminum was vapor-deposited on the nanosheet as a thermal diffusion sacrificial layer.

[0073] Step 5: Using a solvent stripping method to remove the PMMA glue and the upper layer of aluminum, leaving only the aluminum sacrificial layer on the...

[0079] Based on the above-mentioned embodiment 2, this embodiment mainly introduces a nondestructive layer-by-layer etching method with atomic-level precision for a two-dimensional layered material.

[0080] Step 1: Use the mechanical stripping method to remove the MoS to be etched 2 The nanosheets are transferred to silicon wafers.

[0081] Step 2: Repeat steps 2-7 in Example 2 to etch the monolayer along the vertical direction to form strip-shaped thinning regions with vertical periodic structures.

[0082] Step 3: Repeat steps 2-7 in Example 2 to etch the single layer along the horizontal direction to form strip-shaped thinning regions with a horizontal periodic structure.

[0083] Please refer to Figure 8 , Figure 8 In the atomic-level precision non-destructive layer-by-layer etching method of a two-dimensional layered material provided by the present invention, MoS is etched twice along the vertical and horizontal directions. 2 A surface-defined checkerboard pattern...