Deep-Trench Vertical Si Photodiodes for Improved Efficiency and Crosstalk

Author

Mita, Yoshio ; Hirose, Kenichiro ; Kubota, Masanori ; Shibata, Tadashi

Author_Institution

Dept. of Electr. & Electron. Eng., Univ. of Tokyo

Volume

13

Issue

2

fYear

2007

Firstpage

386

Lastpage

391

Abstract

The advancement of deep reactive-ion etching (DRIE) technology has enabled many 3-D structures, and are widely employed in microelectromechanical systems (MEMS). From an electrical point of view, however, those structures have been used as passive components such as capacitors and resistors. To further evolve the utility of future MEMS devices, the authors propose to integrate "active electrical devices" into 3-D MEMS. As an example, vertical trench photodiodes were fabricated on an n-type bulk silicon wafer using DRIE and thermal diffusion of boron. A photocurrent increase from 25% to 70%, and 20% smaller crosstalk was seen in 40-mm deep-trench diodes, as compared to a planar diode made on the same wafer

Keywords

boron; elemental semiconductors; micromechanical devices; optical crosstalk; optical fabrication; photoconductivity; photodiodes; silicon; sputter etching; thermal diffusion; 40 mm; DRIE; Si photodiode; Si:B; boron; crosstalk; deep reactive-ion etching; microelectromechanical systems; photocurrent; thermal diffusion; Capacitors; Crosstalk; Diodes; Etching; Microelectromechanical devices; Microelectromechanical systems; Micromechanical devices; Photodiodes; Resistors; Silicon; Deep reactive-ion etching (DRIE); photo detector; thermal diffusion; trench diode;

fLanguage

English

Journal_Title

Selected Topics in Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

1077-260X

Type

jour

DOI

10.1109/JSTQE.2007.893078

Filename

4159984