Investigation the CMP process of 6 H-SiC in HO solution with ReaxFF molecular dynamics simulation.

To observe the chemical mechanical polishing (CMP) process at the atomic scale, reactive force field molecular dynamics (ReaxFF-MD) was employed to simulate the polishing of 6 H-SiC under three conditions: dry, pure water, and HO solution. This study examined the reactants on the surface of 6 H-SiC during the reaction in the HO solution, along with the dissociation and adsorption processes of HO and water molecules. The mechanisms for atom removal during the CMP process were elucidated.

Fabrication and Polishing Performance of Diamond Self-Sharpening Gel Polishing Disk.

A diamond gel polishing disk with self-sharpening ability is proposed to solve the problem of glazing phenomenon in the gel polishing disks. Aluminum nitride (AlN) powder with silica sol film coating (A/S powder) is added to the polishing disk, and a specific solution is used to dissolve the A/S powder during polishing, forming a pore structure on the polishing disk. To realize the self-sharpening process, the dissolution property of the A/S powder is analyzed.

Soil bacteria around a derelict tailings pile with different metal pollution gradients: community composition, metal tolerance and influencing factors.

Bacteria play a vital role in ecological processes of soil contaminated by heavy metals. Here, soil sampling was carried out around a tailings pile contaminated to different degrees by cadmium (Cd), lead (Pb) and arsenic (As). The bacteria in the soil were cultured, separated and purified on Luria-Bertani medium, and the changes in bacterial communities in soils with different pollution levels were analysed with 16S rRNA sequencing.

Orthogonal Experimental Research on Dielectrophoresis Polishing (DEPP) of Silicon Wafer.

Silicon wafer with high surface quality is widely used as substrate materials in the fields of micromachines and microelectronics, so a high-efficiency and high-quality polishing method is urgently needed to meet its large demand. In this paper, a dielectrophoresis polishing (DEPP) method was proposed, which applied a non-uniform electric field to the polishing area to slow down the throw-out effect of centrifugal force, thereby achieving high-efficiency and high-quality polishing of silicon wafers. The principle of DEPP was described.