Formation of Porous Silicon by Anodizing in Ultrasound Fields

• Published in: Materials science (New York, N.Y.) Vol. 58; no. 1; pp. 89 - 95
• Main Authors: Shepida, M. V., Kuntyi, O. I., Mazur, A. S., Sukhatskyi, Yu. V.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-07-2022; Springer; Springer Nature B.V
• Subjects: Acetonitrile; Anodic dissolution; Anodizing; Characterization and Evaluation of Materials; Chemistry and Materials Science; Dimethylformamide; Dissolution; Electrolysis; Fluorine compounds; Histograms; Hydrofluoric acid; Materials Science; Porous silicon; Silicon; Solid Mechanics; Structural Materials; Substrates; Ultrasonic imaging; porous silicon; silicon anodizing; ultrasound
• ISSN: 1068-820X; 1573-885X
• DOI: 10.1007/s11003-022-00635-5

We present the results of investigations of the electrochemical dissolution of silicon at the anodic potential
E
= 3 V in the field of ultrasound in solutions of hydrofluoric acid (HF) in dimethylsulfoxide (DMSO), dimethylformamide (DMF), and acetonitrile (AN). It is shown that, in the course of anodizing, cylindrical pores with an average diameter of 150 nm are formed on the silicon surface. These pores are uniformly distributed over the substrate. It is shown that the geometry of silicon pores and the rate of their formation are affected by the following main factors: the concentration of HF in the solution, the duration of electrolysis, and the nature of the aprotic solvent. It is shown that the rate of formation of porous silicon (PSi) increases with the HF concentration and the strength of anodic currents. The influence of ultrasound on the process of anodizing is explained. We present the results of scanning electron microscopy and the histograms of distribution of particles in size depending on the conditions of anodic dissolution of silicon.