Etching characteristics of Si{110} in 20 wt% KOH with addition of hydroxylamine for the fabrication of bulk micromachined MEMS
Abstract Anisotropic wet etching is a most widely employed for the fabrication of MEMS/NEMS structures using silicon bulk micromachining. The use of Si{110} in MEMS is inevitable when a microstructure with vertical sidewall is to be fabricated using wet anisotropic etching. In most commonly employed...
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| Format: | Article |
| Language: | English |
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SpringerOpen
2017-05-01
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| Series: | Micro and Nano Systems Letters |
| Subjects: | |
| Online Access: | http://link.springer.com/article/10.1186/s40486-017-0057-7 |
| _version_ | 1818522906627407872 |
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| author | A. V. Narasimha Rao V. Swarnalatha P. Pal |
| author_facet | A. V. Narasimha Rao V. Swarnalatha P. Pal |
| author_sort | A. V. Narasimha Rao |
| collection | DOAJ |
| description | Abstract Anisotropic wet etching is a most widely employed for the fabrication of MEMS/NEMS structures using silicon bulk micromachining. The use of Si{110} in MEMS is inevitable when a microstructure with vertical sidewall is to be fabricated using wet anisotropic etching. In most commonly employed etchants (i.e. TMAH and KOH), potassium hydroxide (KOH) exhibits higher etch rate and provides improved anisotropy between Si{111} and Si{110} planes. In the manufacturing company, high etch rate is demanded to increase the productivity that eventually reduces the cost of end product. In order to modify the etching characteristics of KOH for the micromachining of Si{110}, we have investigated the effect of hydroxylamine (NH2OH) in 20 wt% KOH solution. The concentration of NH2OH is varied from 0 to 20% and the etching is carried out at 75 °C. The etching characteristics which are studied in this work includes the etch rates of Si{110} and silicon dioxide, etched surface morphology, and undercutting at convex corners. The etch rate of Si{110} in 20 wt% KOH + 15% NH2OH solution is measured to be four times more than that of pure 20 wt% KOH. Moreover, the addition of NH2OH increases the undercutting at convex corners and enhances the etch selectivity between Si and SiO2. |
| first_indexed | 2024-12-11T05:38:54Z |
| format | Article |
| id | doaj.art-433e8aa64ff7426c930b123c88f784cb |
| institution | Directory Open Access Journal |
| issn | 2213-9621 |
| language | English |
| last_indexed | 2024-12-11T05:38:54Z |
| publishDate | 2017-05-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Micro and Nano Systems Letters |
| spelling | doaj.art-433e8aa64ff7426c930b123c88f784cb2022-12-22T01:19:12ZengSpringerOpenMicro and Nano Systems Letters2213-96212017-05-01511910.1186/s40486-017-0057-7Etching characteristics of Si{110} in 20 wt% KOH with addition of hydroxylamine for the fabrication of bulk micromachined MEMSA. V. Narasimha Rao0V. Swarnalatha1P. Pal2MEMS and Micro/Nano Systems Laboratory, Department of Physics, Indian Institute of Technology HyderabadMEMS and Micro/Nano Systems Laboratory, Department of Physics, Indian Institute of Technology HyderabadMEMS and Micro/Nano Systems Laboratory, Department of Physics, Indian Institute of Technology HyderabadAbstract Anisotropic wet etching is a most widely employed for the fabrication of MEMS/NEMS structures using silicon bulk micromachining. The use of Si{110} in MEMS is inevitable when a microstructure with vertical sidewall is to be fabricated using wet anisotropic etching. In most commonly employed etchants (i.e. TMAH and KOH), potassium hydroxide (KOH) exhibits higher etch rate and provides improved anisotropy between Si{111} and Si{110} planes. In the manufacturing company, high etch rate is demanded to increase the productivity that eventually reduces the cost of end product. In order to modify the etching characteristics of KOH for the micromachining of Si{110}, we have investigated the effect of hydroxylamine (NH2OH) in 20 wt% KOH solution. The concentration of NH2OH is varied from 0 to 20% and the etching is carried out at 75 °C. The etching characteristics which are studied in this work includes the etch rates of Si{110} and silicon dioxide, etched surface morphology, and undercutting at convex corners. The etch rate of Si{110} in 20 wt% KOH + 15% NH2OH solution is measured to be four times more than that of pure 20 wt% KOH. Moreover, the addition of NH2OH increases the undercutting at convex corners and enhances the etch selectivity between Si and SiO2.http://link.springer.com/article/10.1186/s40486-017-0057-7Wet anisotropic etchingBulk micromachiningSiliconCorner undercuttingKOHMEMS |
| spellingShingle | A. V. Narasimha Rao V. Swarnalatha P. Pal Etching characteristics of Si{110} in 20 wt% KOH with addition of hydroxylamine for the fabrication of bulk micromachined MEMS Micro and Nano Systems Letters Wet anisotropic etching Bulk micromachining Silicon Corner undercutting KOH MEMS |
| title | Etching characteristics of Si{110} in 20 wt% KOH with addition of hydroxylamine for the fabrication of bulk micromachined MEMS |
| title_full | Etching characteristics of Si{110} in 20 wt% KOH with addition of hydroxylamine for the fabrication of bulk micromachined MEMS |
| title_fullStr | Etching characteristics of Si{110} in 20 wt% KOH with addition of hydroxylamine for the fabrication of bulk micromachined MEMS |
| title_full_unstemmed | Etching characteristics of Si{110} in 20 wt% KOH with addition of hydroxylamine for the fabrication of bulk micromachined MEMS |
| title_short | Etching characteristics of Si{110} in 20 wt% KOH with addition of hydroxylamine for the fabrication of bulk micromachined MEMS |
| title_sort | etching characteristics of si 110 in 20 wt koh with addition of hydroxylamine for the fabrication of bulk micromachined mems |
| topic | Wet anisotropic etching Bulk micromachining Silicon Corner undercutting KOH MEMS |
| url | http://link.springer.com/article/10.1186/s40486-017-0057-7 |
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