Photodetector on Silicon. Heng Yang. Outline. Introduction Si Photodetector in 770 ~ 850 nm Range IR Schottky barrier photodetector. Introduction. Essentially - p-n diode under the reverse bias Operate in the photoconductive mode Main usage - for the conversion of the optical signal
J = Jdrfit + Jdiff
Interdigitated electrodes are often used to increase the active region area while optimizing the electric fields in the carrier collection region.
Electrode can either be P+/N+ or just metal.
Finger space = 3.3 mm
Trench depth = 8 mm
Finger size = 0.35 mm
For l=845 nm,
BW=1.5 GHz, Responsivity = 0.47 A/W at 5V
Min Yang, Kern Rim, Dennis L. Rogers, et al., IEEE ELECTRON DEVICE LETTERS, VOL. 23, NO. 7, JULY 2002
For l = 790 nm, BW = 2.2 GHz, Responsivity = 0.14 A/W @ 5V
Jacob Y. L. Ho and K. S. Wong, IEEE Photonics Technology Letters, 8(8), 1996
Three pair of quarter wavelength SiO2 and polysilicon at bottom (LPCVD).
Etched seed window.
SiO2 Side-wall to prevent defects at the edge of poly.
Two pairs of ZnSe-MgF on top (evaporated).
J. D. Schaub, R. Li, C. L. Schow, J. C. Campbell, G. W. Neudeck, and J. Denton
,IEEE PHOTONICS TECHNOLOGY LETTERS, VOL. 11, NO. 12, DECEMBER 1999
M. Y. Liu, E. Chen, and S. Y. Chou, Appl. Phys. Lett. 65 (7), 15 August 1994
300,000 PtSi/p-Si Schottky barrier IR detector focal plane arrays have been developed and used on Air Force B-52
High lC gives high QE. In order to expand the spectrum, efforts were made to decrease the barrier height.
Masafumi Kimata, Tatsuo Ozaki, Natsuro Tsubouchi and Sho Ito, Proceeding of SPIE, 1998
TL Lin, JS Park et al.
Appl. Phys. Lett. 62(25), 1993
Farshid Raissi and Mansoor Mohtashami Far, IEEE Sensors Journal, 2 (5) 2002