1 / 14

Fabrication of Silicon Probes for Biosensors

Fabrication of Silicon Probes for Biosensors. Dr. Marcelo Bariatto A. Fontes (Post-Doc) LSI / USP Dr. Rogério Furlan LSI / USP Dr. Jorge J. Santiago-Avilés UPENN. MOTIVATION. Biological applications neural activities

taima
Télécharger la présentation

Fabrication of Silicon Probes for Biosensors

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Fabrication of Silicon Probes for Biosensors Dr. Marcelo Bariatto A. Fontes (Post-Doc) LSI / USP Dr. Rogério Furlan LSI / USP Dr. Jorge J. Santiago-Avilés UPENN

  2. MOTIVATION • Biological applications • neural activities • intracellular recording • ionic distribution • electrical stimulation http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  3. MICROPROBE FABRICATION • Glass micropipette • Carbon • Metal • Single electrode • Low reproducibility http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  4. SILICON MICROMACHINED PROBES • Easy shape definition by computer-designed photomask • Multidetection and spatial distribution • High reproducibility • IC compatible (smart sensors) • Batch fabrication and • Low cost http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  5. MICROMACHINING TECHNIQUES • Deep boron diffusion • high temperature and time • Lateral diffusion • “large”dimensions • Strong crystal orientation dependence • Boron etch stop • Plasma etching • Low temperature process • Better shape definition and thickness control • without lateral diffusion • Quick process • Low silicon crystalline orientation dependence http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  6. PROBE DESIGN • Needle shape general purpose electrochemical system • Multipoint and multispecies detection • 2 to10 gold µelectrodes • 90 to 340 µm tip Ag/AgCl reference Platinum auxiliary http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  7. FABRICATION STEPS • Boron etch stop mask 3 mask 1 mask 1 mask 2 mask 1 • Plasma etching mask 1  probe shape mask 2  lines / contacts mask 3  windows http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  8. FABRICATION RESULTS - SEM and AFM • High reproducibility • Roughness :12.5 nm (rms) • 16 %  area http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  9. FABRICATION RESULTS - Si PROBES • Etch stop SIMS analyses [B]=1.25 1020at./cm3 • Plasma etching http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  10. FABRICATION RESULTS - COMPLETE SEQUENCE • Uncompensated mechanical stress • coverage and lines damaged http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  11. FABRICATION RESULTS - FINAL DEVICE http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  12. CONCLUSION • High reproducible micromachined multidetection silicon probe (80%) • Several probe designs were explored by varying the number of the detection electrodes • Plasma etching technique presented better characteristics of shape definition and processing time than “etch stop” • Boron etch stop  2.4x1019 at./cm3 (SIMS) http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  13. CONCLUSION - cont. • Plain silicon probes of 15 µm were obtained • Uncompensated mechanical stress between SiO2 and Si3N4 • Bent structures  decrease the processing yield • Increase of probe thickness by plasma etching  45 µm • Compatibility with silicon microelectronic technology • New materials for interconnection and coverage (Poly-Si / Polymers) http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

  14. ACKNOWLEDGMENTS • CNPq • FAPESP • CNPq/PADCT/CDCT • Center for Sensor Technology at UPENN http://www.lsi.usp.br/~bariatto/ SBmicro 2000 - Manaus - Amazonas

More Related