2010 Device Research Conference Presentation-Record Current Density Esaki Diodes

1. Sub-Micron InGaAs Esaki Diodes With Record High Peak Current Density D. Pawlik, M. Barth, P. Thomas, S. Kurinec, S. Rommel S. Mookerjea, D. Mohata, S. Datta S. Cohen, D. Ritter This work is partially supported by NSF (ECCS-0725760) Device Research Conference: June 22, 2010

3. Valley Current: JV = IV/Area

4. Peak-to-Valley current ratio: PVCRJV - VP VV

6. Operated in Zener direction

7. High JZ needed for drive current

8. Scaled to deep sub-micron dimensionsSource P++ i Gate Multijunction Solar CellsTunneling SRAMBJT & Contacts n++ Tunnel Junction Drain Tunnel Diodes website:www.sustainability.rit.edu/nanopower/ E. Yalon, et Al., DRC 2010

11. Higher level of doping than TD2

12. Contact layers: reduced doping

13. MOMBE Grown at Technion, Haifa, Israel

14. Lower Doping than TD1

16. Defined by E-Beam lithography

17. Au/Zn/Au (20nm/20nm/160nm)

18. Mesa Isolation Etch

19. Citric Acid : H2O2 (20:1)

20. ~80 nm deep

21. ~20 nm below the junction200 nm 200 nm

25. ~25,200 mm2

26. Current Scales with area

27. PVCRTD2 > PVCRTD1

28. JTD1 > JTD2Preliminary Results

30. Deviations from trendline are likely due to uncertainties in area

31. Devices measured: 200+ each

32. Gaussian fit used to determine JP

34. Current Density vs. N*

36. Effects: Apparent (false) reduction in JZ

37. Smaller currents result in smaller shifts

39. RC is the slope of VP vs. IP(2) Area dependent (rArea)

41. RC constant V shift

42. rA variable V shift y  m * x

44. Junctions as small as ~0.015 mm2(R = 69 nm) were fabricated.

45. Degradation of JP and JZ were not directly observed

46. Sub-micron junctions needed to minimize RSeries effects

47. RSerieswas characterized

48. Highest reported JP of 9.75 mA/mm2 for any tunnel diode was measured