Deep reactive ion etching of Si-based materials Oxford Instruments Plasma Technology PlasmaPro 100 (DRIE)

Deep reactive-ion etching (DRIE) is a highly anisotropic etch process used to create deep penetration, steep-sided holes, and trenches in wafers/substrates, typically with high aspect ratios. It was developed for microelectromecha­nical systems (MEMS), which require these features, but is also used to excavate trenches for high-density capacitors for DRAM and more recently for creating through silicon via´s (TSV)´s in advanced 3D wafer-level packaging technology.
There are two main technologies for high-rate DRIE: cryogenic and Bosch, although the Bosch process is the only recognized production technique. Both Bosch and cryo processes can fabricate 90° (truly vertical) walls, but often the walls are slightly tapered, e.g. 88° („reentrant“) or 92° („retrograde“).
Another mechanism is sidewall passivation: SiOxFy functional groups (which originate from sulfur hexafluoride and oxygen etch gases) condense on the sidewalls and protect them from lateral etching. As a combination of these processes deep vertical structures can be made.

Publications:

• CHMELÍKOVÁ, L.; FECKO, P.; CHMELÍK, J.; SKÁCEL, J.; OTÁHAL, A.; FOHLEROVÁ, Z., 2023: Demolded hollow high aspect-ratio parylene-C micropillars for real-time mechanosensing applications. APPLIED MATERIALS TODAY , p. 1 - 12, doi: 10.1016/j.apmt.2023.101736; FULL TEXT
  (DRIE, PARYLENE-SCS, SUSS-MA8, XEF2)
• Mahel, V., 2023: Variable MEMS aperture for electron microscopy. MASTER´S THESIS ; FULL TEXT
  (DWL, DRIE, DEKTAK, DIENER, WIRE-BONDER)
• GABLECH, I.; BRODSKÝ, J.; VYROUBAL, P.; PIASTEK, J.; BARTOŠÍK, M.; PEKÁREK, J., 2022: Mechanical strain and electric-field modulation of graphene transistors integrated on MEMS cantilevers. JOURNAL OF MATERIALS SCIENCE 57(3), p. 1923 - 13, doi: 10.1007/s10853-021-06846-6; FULL TEXT
  (RIE-FLUORINE, DRIE, EVAPORATOR, WIRE-BONDER, WITEC-RAMAN, MPS150, KEITHLEY-4200, SUSS-MA8, DWL)
• Ondříšková, M., 2022: Analysis and characterisation of spirally–arranged field–emission nanostructure. BACHELOR´S THESIS , p. 1 - 56; FULL TEXT
  (VERIOS, DRIE, KRATOS-XPS)
• Brodský J., 2021: Gas sensors based on 1D and 2D materials. MASTER´S THESIS , p. 1 - 84; FULL TEXT
  (DWL, DIENER, SUSS-RCD8, SUSS-MA8, EVAPORATOR, MPS150, WITEC-RAMAN, RIE-FLUORINE, DRIE, LYRA, ICON-SPM)

• LIU, X.; FECKO, P.; FOHLEROVÁ, Z.; PEKÁREK, J.; KARÁSEK, T.; NEUŽIL, P., 2020: Parylene Micropillars Coated with Thermally Grown SiO2. JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B 38(6), p. 38 - 6, doi: 10.1116/6.0000558; FULL TEXT
  (SUSS-MA8, SUSS-RCD8, DWL, DRIE, RIE-FLUORINE, PARYLENE-SCS, XEF2, APCVD, LYRA)
• GABLECH, I.; KLEMPA, J.; PEKÁREK, J.; VYROUBAL, P.; HRABINA, J.; HOLÁ, M.; KUNZ, J.; BRODSKÝ, J.; NEUŽIL, P., 2020: Simple and efficient AlN-based piezoelectric energy harvesters. MICROMACHINES 11(2), p. 1 - 10, doi: 10.3390/mi11020143; FULL TEXT
  (DRIE, RIE-CHLORINE, WIRE-BONDER, KAUFMAN)
• Fecko, P., 2019: Gecko mimicking surfaces. MASTER´S THESIS , p. 1 - 52
  (SUSS-RCD8, SUSS-MA8, DWL, DRIE, ALD, RIE-FLUORINE, PARYLENE-SCS, XEF2, LYRA, ICON-SPM)
• Brodský, J., 2019: Characterization of graphene elecrical properties on MEMS structures. BACHELOR´S THESIS , p. 1 - 50
  (MPS150, WITEC-RAMAN, EVAPORATOR, DRIE, PECVD, DWL, SUSS-MA8, RIE-FLUORINE, RIE-CHLORINE, DIENER, SCIA)
• PRÁŠEK, J.; HOUŠKA, D.; HRDÝ, R.; HUBÁLEK, J.; SCHMID, U., 2019: Optimization of Cryogenic Deep Reactive Ion Etching Process for On-Chip Energy Storage. INTERNATIONAL SPRING SEMINAR ON ELECTRONICS TECHNOLOGY ISSE , p. 1 - 6, doi: 10.1109/ISSE.2019.8810293; FULL TEXT
  (DRIE, SUSS-MA8, SUSS-RCD8, EVAPORATOR, DWL, ICON-SPM)
• GABLECH, I.; KLEMPA, J.; PEKÁREK, J.; VYROUBAL, P.; KUNZ, J.; NEUŽIL, P., 2019: Aluminum nitride based piezoelectric harvesters. 2019 19TH INTERNATIONAL CONFERENCE ON MICRO AND NANOTECHNOLOGY FOR POWER GENERATION AND ENERGY CONVERSION APPLICATIONS (POWERMEMS) (001), p. 1 - 4, doi: 10.1109/PowerMEMS49317.2019.82063211368; FULL TEXT
  (DIENER, DRIE, DWL, KAUFMAN, RIE-CHLORINE, SUSS-MA8)
• GABLECH, I.; SOMER, J.; FOHLEROVÁ, Z.; SVATOŠ, V.; PEKÁREK, J.; KURDÍK, S.; FENG, J.; FECKO, P.; PODEŠVA, P.; HUBÁLEK, J.; NEUŽIL, P., 2018: Fabrication of buried microfluidic channels with observation windows using femtosecond laser photoablation and parylene-C coating. MICROFLUIDICS AND NANOFLUIDICS 22(9), p. NA - 7, doi: 10.1007/s10404-018-2125-6; FULL TEXT
  (DRIE, DWL, SUSS-MA8, PARYLENE-SCS, XEF2)