US 11,927,839 B2
Broadband electro-absorption optical modulator using on-chip RF input signal termination
Andrei Kaikkonen, Jarfalla (SE); David Adams, Stockholm (SE); Robert Lewen, Tyreso (SE); and Nicolae Chitica, Kista (SE)
Assigned to II-VI Delaware, Inc., Wilmington, DE (US)
Filed by II-VI Delaware, Inc., Wilmington, DE (US)
Filed on Sep. 14, 2020, as Appl. No. 17/019,706.
Prior Publication US 2022/0082874 A1, Mar. 17, 2022
Int. Cl. H01S 5/06 (2006.01); G02F 1/025 (2006.01); G02F 1/015 (2006.01)
CPC G02F 1/025 (2013.01) [H01S 5/0601 (2013.01); G02F 1/0157 (2021.01); G02F 2202/101 (2013.01); G02F 2202/102 (2013.01); G02F 2202/108 (2013.01)] 10 Claims
OG exemplary drawing
 
1. An electro-absorption optical modulator comprising
a substrate of a first conductivity type, the substrate defined as comprising a top major surface;
an electro-absorption modulating device formed along a longitudinal extent of the substrate, the electro-absorption modulating device including an active layer and an optical waveguiding layer of a second conductivity type disposed over the active layer, the optical waveguiding layer configured to receive an incoming continuous wave (CW) optical signal and generate an optically modulated output signal therefrom;
a dielectric layer disposed on a portion of the top major surface of the substrate at a spaced-apart location separate from the electro-absorption modulating device;
a conductive layer disposed over the dielectric layer, wherein the combination of the substrate, the dielectric layer and the conductive layer form a distributed capacitance within the electro-absorption optical modulator;
a stripline conductor disposed over an extended portion of the optical waveguiding layer;
an RF signal input path coupled to the stripline conductor for providing an electrical input RF modulating signal to the electro-absorption modulating device; and
a resistive RF signal termination path coupled between the stripline conductor and the conductive layer, the conductive layer providing an AC ground termination for the electrical input RF modulating signal of the electro-absorption optical modulator.