Wet Oxidation and Hydrogen Incorporation on 4H-SiC
Description: Wet Oxidation and Hydrogen Incorporation on 4H-SiC (c-face) Can Xu1, Voshadhi Amarasinghe1, Gang Liu1, Boris Yakshinskiy1, Sarit Dhar2, Torgny Gustafsson1, Joseph Bloch1 and Leonard Feldman1 1Institute of Advance Materials, Devices and
Related Topics
Download Presentation
"Wet Oxidation and Hydrogen Incorporation on 4H-SiC" is the property of its rightful owner. Permission is granted to download and print the materials on this website for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Presentation Transcript
slide1. Wet Oxidation and Hydrogen Incorporation on 4H-SiC (c-face) Can Xu1, Voshadhi Amarasinghe1, Gang Liu1, Boris Yakshinskiy1,
Sarit Dhar2, Torgny Gustafsson1, Joseph Bloch1 and Leonard Feldman1
1Institute of Advance Materials, Devices and Nanotechnology (IAMDN), Rutgers University
2Department of Physics, Auburn University<br>
slide2. Motivation 2 Dieter K. Schroder, Electrical Characterization of Defects in Gate Dielectrics Hydrogen reduces the interface defect density in Si MOS devices.
Effect on SiC?
Questions to answer:
Is there hydrogen at the interface?
Hydrogen vs. defect?
Hydrogen vs. electrical properties? Water uptake during device processing
Does hydrogen go into the oxide/interface during device processing?
Does this result in a electrical degradation?<br>
slide3. Effect of pyrogenic oxidation (H2+O2) on Dit & µFE 3 Wet oxidation: temperature Dit M. Okamoto et al. Appl. Phys. Express 5, 2012, 041302<br>
slide4. Effect of pyrogenic oxidation (H2+O2) on Dit & µFE 4 Wet oxidation: temperature Dit
Post oxidation H2 anneal: Dit M. Okamoto et al. Appl. Phys. Express 5, 2012, 041302<br>
slide5. Effect of pyrogenic oxidation (H2+O2) on Dit & µFE 5 Wet oxidation: temperature Dit
Post oxidation H2 anneal: Dit M. Okamoto et al. Appl. Phys. Express 5, 2012, 041302 Post oxidation H2 anneal: µFE<br>
slide6. Effect of hydrogen anneals on Dit 6 S. Wang et al. PRL 98 , 2007, 026101 Effect of H2 annealing at 500° C for Pt gated oxide Final outcome:
NO anneal reduced higher energy defects closer to Ec
H2 anneal reduce defects deeper into the gap
NO + H2 anneal reduced the defect density throughout the 0.2-1.6 eV range<br>
slide7. Effect of hydrogen anneals on Dit 7 S. Wang et al. PRL 98 , 2007, 026101 Effect of H2 annealing at 500° C for Pt gated oxide Final outcome:
NO anneal reduced higher energy defects closer to Ec
H2 anneal reduce defects deeper into the gap
NO + H2 anneal reduced the defect density throughout the 0.2-1.6 eV range<br>
slide8. Effect of hydrogen anneals on Dit 8 S. Wang et al. PRL 98 , 2007, 026101 Effect of H2 annealing at 500° C for Pt gated oxide Final outcome:
NO anneal reduced higher energy defects closer to Ec
H2 anneal reduce defects deeper into the gap
NO + H2 anneal reduced the defect density throughout the 0.2-1.6 eV range<br>
slide9. Nuclear Reaction analysis (NRA) 9 Sensitivity to 2 x 1012 atoms/cm2 (0.1% of a monolayer)<br>
slide10. Summary of “D” uptake by 4H-SiC faces vs Si 10 Liu et al. Appl. Phys. Lett. 106, 2015, 123502 Interface D content: after annealing dry oxide in D2O at 400° C for 15 hrs SiC<br>
slide11. Summary of “D” uptake by 4H-SiC faces vs Si 11 Flat band voltage shift is proportional to the interface “D” C-face NO a-face O2 C-face O2 C-face Ar<br>
slide12. Relationship between wet oxidation and interface “D” concentration<br>
slide13. Wet oxidation 13 Oxidation at different temp. using D2O D D D D Stripping oxide followed by NRA<br>
slide14. Wet oxidation 14 Oxidation at different temp. using D2O D D D D Stripping oxide followed by NRA The less D retained at the interface during
wet oxidation, the better Nit D content ( x 1013 /cm3) Nit ( x 1012)<br>
slide15. Post oxidation D2 anneal 15 D2 exposure at different temp. C-V and NRA analysis Wet oxidation at 1000° C D D D D D D D D<br>
slide16. Post oxidation D2 anneal 16 D2 exposure at different temp. C-V and NRA analysis Wet oxidation at 1000° C D D D D Post oxidation anneal improves the interface, and the
defect density is inversely proportional to the D amount D D D D D content ( x 1014 /cm3) Nit ( x 1012)<br>
slide17. Temperature dependent “D” uptake by exposure to D2O from the SiO2(dry)/SiC interface<br>
slide18. Temperature dependent water uptake 18 D2O exposure at different temp. Stripping oxide
followed by NRA Oxidation at 1150° C D D D D<br>
slide19. Temperature dependent water uptake 19 D2O exposure at different temp. Stripping oxide
followed by NRA Oxidation at 1150° C D D D D x x x x wet oxidation D concentration 850° C wet 900° C wet 1000° C wet D uptake is maximal at 700 °C<br>
slide20. Temperature dependent water uptake 20 D2O exposure at different temp. Stripping oxide
followed by NRA Oxidation at 1150° C D D D D H passivation of Pb defect on Si(111) x x x x wet oxidation D concentration 850° C wet 900° C wet 1000° C wet<br>
slide21. Effect of NO passivation on “D” uptake 21<br>
slide22. Effect of NO passivation on “D” uptake 22 NO passivation significantly reduce the interface “D” at the SiO2/SiC interface<br>
slide23. Conclusions 23 Our quantification of D content with temperature, in combination with electrical measurements, suggest there is a optimum D content, hence the need to control temperature.
D uptake is maximal at 700 °C
At high temperatures: D incorporation during wet oxidation and post dry + D2O annealing similarity suggest that “D” atoms bond to similar sites.
D uptake as function of temperature is consistent with combined “up-take” and “loss” chemical processes, as previously identified for Si, but with characteristic temperatures substantially higher for SiC.<br>
slide24. Questions and comments<br>
slide25. Interfacial D content (c-f) vs Vfb 25<br>
Sarit Dhar2, Torgny Gustafsson1, Joseph Bloch1 and Leonard Feldman1
1Institute of Advance Materials, Devices and Nanotechnology (IAMDN), Rutgers University
2Department of Physics, Auburn University<br>
slide2. Motivation 2 Dieter K. Schroder, Electrical Characterization of Defects in Gate Dielectrics Hydrogen reduces the interface defect density in Si MOS devices.
Effect on SiC?
Questions to answer:
Is there hydrogen at the interface?
Hydrogen vs. defect?
Hydrogen vs. electrical properties? Water uptake during device processing
Does hydrogen go into the oxide/interface during device processing?
Does this result in a electrical degradation?<br>
slide3. Effect of pyrogenic oxidation (H2+O2) on Dit & µFE 3 Wet oxidation: temperature Dit M. Okamoto et al. Appl. Phys. Express 5, 2012, 041302<br>
slide4. Effect of pyrogenic oxidation (H2+O2) on Dit & µFE 4 Wet oxidation: temperature Dit
Post oxidation H2 anneal: Dit M. Okamoto et al. Appl. Phys. Express 5, 2012, 041302<br>
slide5. Effect of pyrogenic oxidation (H2+O2) on Dit & µFE 5 Wet oxidation: temperature Dit
Post oxidation H2 anneal: Dit M. Okamoto et al. Appl. Phys. Express 5, 2012, 041302 Post oxidation H2 anneal: µFE<br>
slide6. Effect of hydrogen anneals on Dit 6 S. Wang et al. PRL 98 , 2007, 026101 Effect of H2 annealing at 500° C for Pt gated oxide Final outcome:
NO anneal reduced higher energy defects closer to Ec
H2 anneal reduce defects deeper into the gap
NO + H2 anneal reduced the defect density throughout the 0.2-1.6 eV range<br>
slide7. Effect of hydrogen anneals on Dit 7 S. Wang et al. PRL 98 , 2007, 026101 Effect of H2 annealing at 500° C for Pt gated oxide Final outcome:
NO anneal reduced higher energy defects closer to Ec
H2 anneal reduce defects deeper into the gap
NO + H2 anneal reduced the defect density throughout the 0.2-1.6 eV range<br>
slide8. Effect of hydrogen anneals on Dit 8 S. Wang et al. PRL 98 , 2007, 026101 Effect of H2 annealing at 500° C for Pt gated oxide Final outcome:
NO anneal reduced higher energy defects closer to Ec
H2 anneal reduce defects deeper into the gap
NO + H2 anneal reduced the defect density throughout the 0.2-1.6 eV range<br>
slide9. Nuclear Reaction analysis (NRA) 9 Sensitivity to 2 x 1012 atoms/cm2 (0.1% of a monolayer)<br>
slide10. Summary of “D” uptake by 4H-SiC faces vs Si 10 Liu et al. Appl. Phys. Lett. 106, 2015, 123502 Interface D content: after annealing dry oxide in D2O at 400° C for 15 hrs SiC<br>
slide11. Summary of “D” uptake by 4H-SiC faces vs Si 11 Flat band voltage shift is proportional to the interface “D” C-face NO a-face O2 C-face O2 C-face Ar<br>
slide12. Relationship between wet oxidation and interface “D” concentration<br>
slide13. Wet oxidation 13 Oxidation at different temp. using D2O D D D D Stripping oxide followed by NRA<br>
slide14. Wet oxidation 14 Oxidation at different temp. using D2O D D D D Stripping oxide followed by NRA The less D retained at the interface during
wet oxidation, the better Nit D content ( x 1013 /cm3) Nit ( x 1012)<br>
slide15. Post oxidation D2 anneal 15 D2 exposure at different temp. C-V and NRA analysis Wet oxidation at 1000° C D D D D D D D D<br>
slide16. Post oxidation D2 anneal 16 D2 exposure at different temp. C-V and NRA analysis Wet oxidation at 1000° C D D D D Post oxidation anneal improves the interface, and the
defect density is inversely proportional to the D amount D D D D D content ( x 1014 /cm3) Nit ( x 1012)<br>
slide17. Temperature dependent “D” uptake by exposure to D2O from the SiO2(dry)/SiC interface<br>
slide18. Temperature dependent water uptake 18 D2O exposure at different temp. Stripping oxide
followed by NRA Oxidation at 1150° C D D D D<br>
slide19. Temperature dependent water uptake 19 D2O exposure at different temp. Stripping oxide
followed by NRA Oxidation at 1150° C D D D D x x x x wet oxidation D concentration 850° C wet 900° C wet 1000° C wet D uptake is maximal at 700 °C<br>
slide20. Temperature dependent water uptake 20 D2O exposure at different temp. Stripping oxide
followed by NRA Oxidation at 1150° C D D D D H passivation of Pb defect on Si(111) x x x x wet oxidation D concentration 850° C wet 900° C wet 1000° C wet<br>
slide21. Effect of NO passivation on “D” uptake 21<br>
slide22. Effect of NO passivation on “D” uptake 22 NO passivation significantly reduce the interface “D” at the SiO2/SiC interface<br>
slide23. Conclusions 23 Our quantification of D content with temperature, in combination with electrical measurements, suggest there is a optimum D content, hence the need to control temperature.
D uptake is maximal at 700 °C
At high temperatures: D incorporation during wet oxidation and post dry + D2O annealing similarity suggest that “D” atoms bond to similar sites.
D uptake as function of temperature is consistent with combined “up-take” and “loss” chemical processes, as previously identified for Si, but with characteristic temperatures substantially higher for SiC.<br>
slide24. Questions and comments<br>
slide25. Interfacial D content (c-f) vs Vfb 25<br>