Design of a multi-GHz SiGe HBT EO modulator

Shengling Deng; Tuhin Guha Neogi; J. F. McDonald; Joseph Novak; Z. Rena Huang

doi:10.1117/12.843269

23 February 2010 Design of a multi-GHz SiGe HBT EO modulator

Shengling Deng, Tuhin Guha Neogi, J. F. McDonald, Joseph Novak, Z. Rena Huang

Proceedings Volume 7607, Optoelectronic Interconnects and Component Integration IX; 760710 (2010) https://doi.org/10.1117/12.843269
Event: SPIE OPTO, 2010, San Francisco, California, United States

Abstract

Silicon-based electro-optic (EO) modulator is an indispensable building block for integrated lightwave circuits. In this paper, we report an EO modulator that incorporates a heterojunction bipolar transistor (HBT) with Ge composition graded base. The emitter is n-type doped silicon with a doping concentration of 10²¹/cm³. The width of the emitter strip is 0.2μm and the thickness of the emitter layer is 0.16μm. The base has a thickness of 40nm with varying Ge composition from zero at the emitter-base junction side to 20% at the base-collector junction side. Raised extrinsic base is incorporated for base contact. The intrinsic base is p-type doped with a concentration of 4×10¹⁹/cm³. The HBT is biased at V_CE = 0.5 V whereas VBE is switched between -1.0V and 1.0V. The carrier distribution at "ON" state of the EO modulator and the transient analysis are performed by MEDCI simulation. The changes of the refractive indices of the HBT are computed from the carrier density in all regions, and then the refractive index map is imported into an optical mode solver (RSoft BeamProp). The HBT EO modulator that supports only one optical mode is ideal, but a trade-off between modal property and device speed is observed. For current design, we achieved a π-phase modulation length of less than 600μm, and a switching delay less than 62ps.

Citation Download Citation

Shengling Deng, Tuhin Guha Neogi, J. F. McDonald, Joseph Novak, and Z. Rena Huang "Design of a multi-GHz SiGe HBT EO modulator", Proc. SPIE 7607, Optoelectronic Interconnects and Component Integration IX, 760710 (23 February 2010); https://doi.org/10.1117/12.843269

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available