Abstract
Specimens of n-type single crystalline silicon sparsely deposited with silver nano-particles on the Si (100) surfaces were put in 1.0 M NH 4F + 5.0 M H 2O 2 to investigate their dark etching. Through examination by scanning electron microscopy (SEM), the morphology on the n-Si (100) surface etched for 1 h revealed a sparse distribution of nano-pores (10~40 nm in diameter) according to the locations of Ag-particles; however, it exhibited porous surface consisting of micro-pores (1.5~3.1μm in diameter with 15~20μm in depth) where nano-pores (100~150 nm in diameter) were embedded inside for the etching duration prolonged for 5 h. The Nyquist plot for this system indicated two typical semicircles, in which the one in response to high frequencies revealed greater diameter and the other in response to low frequencies indicated smaller diameter. By checking the chemical bonding of silicon and silica in the NH 4F/H 2O 2 system shows two important points at 99.3 eV and 103.4 eV.
Original language | English |
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Pages (from-to) | 6846-6858 |
Number of pages | 13 |
Journal | International Journal of Electrochemical Science |
Volume | 7 |
Issue number | 8 |
State | Published - Aug 2012 |
Keywords
- Ammonium fluoride
- Energy band diagram
- Metal-assist etch
- Porous silicon