Fig. 1.
Prestructuring process for both sides of the silicon wafer.
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| Citation: |
Yaohu Lei, Zhigang Zhao, Jinchuan Guo, Ji Li, Hanben Niu. Disordered wall arrays by photo-assisted electrochemical etching in n-type silicon[J]. Journal of Semiconductors, 2016, 37(10): 106001. doi: 10.1088/1674-4926/37/10/106001
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Y H Lei, Z G Zhao, J C Guo, J Li, H B Niu. Disordered wall arrays by photo-assisted electrochemical etching in n-type silicon[J]. J. Semicond., 2016, 37(10): 106001. doi: 10.1088/1674-4926/37/10/106001.
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Disordered wall arrays by photo-assisted electrochemical etching in n-type silicon
DOI: 10.1088/1674-4926/37/10/106001
More Information
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Abstract
The fabrication of ordered, high aspect-ratio microstructures in silicon by use of photo-assisted electrochemical etching is an important technology, where voltage and current density are significant factors. In this paper, disordered walls appear in 5-inch n-type silicon wafers when a large current density is used. Based on the theory of space charge region, these disordered walls are caused by the contradiction between the protection from dissolution by a high applied voltage and the dissolution by a high current density. To verify this point, wall arrays were fabricated at different applied voltages and current densities. Moreover, the critical voltage was kept constant and different current densities were applied to obtain conditions for avoiding disordered walls and achieving uniform wall arrays. Finally, a wall array with a period of 5.6μm and a depth of 55μm was achieved at an applied voltage of 3 V and a monotonically increasing current density ranging from 22.9 to 24.5 mA/cm2.-
Keywords:
- electrochemical etching,
- wall array,
- high aspect-ratio,
- silicon,
- disordered wall
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References
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