# US 2019/0171044 A1 · Electro-optic modulator > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0171044 A1 - Document ID: US20190171044A1 - Status: Published application - Kind: A1 - Application number: 16/252,450 - Filed: 2019-01-18 - Published: 2019-06-06 - Earliest claimed: 2016-07-21 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Yanbo Li; Xiaolu Song; Zhen Dong; Ruiqiang Ji; Shengmeng Fu; Li Zeng - Web page: https://patentgrep.com/patent/US20190171044A1 ## CPC - G02F 1/025: in an optical waveguide structure (G02F1/017, {G02F1/2257} take precedence) - G02F 1/015: based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction (G02F1/03 takes precedence) - G02F 1/0151: {modulating the refractive index} - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS ## Abstract An electro-optic modulator includes an input waveguide, a beam splitter connected to the input waveguide, a modulation arm that is disposed on each branch of the beam splitter and modulates a signal. Each modulation arm is correspondingly disposed with a first layer electrode and a second layer electrode. The first layer electrode is a high-frequency traveling wave electrode and is configured to change carrier concentration in the modulation arm, the second layer electrode is a direct current electrode having an inductor function, and an inductor formed in the second layer electrode is connected to the first layer electrode. The electro-optic modulator has functions of a bias tee, so that integration of the electro-optic modulator can be improved without affecting its performance. High-density packaging layout difficulty and cabling pressure can be effectively reduced, and cabling and packaging of a multi-channel high-speed signal on a base board can be implemented. ## Claims ### Claim 1 An electro-optic modulator, comprising: an input waveguide; a beam splitter connected to the input waveguide; a modulation arm disposed on each branch of the beam splitter and configured to modulate a signal; a beam combiner connected to each branch of the beam splitter and configured to combine signals; and an output waveguide connected to the beam combiner, wherein each modulation arm is correspondingly disposed with a double-layer electrode comprising, a first layer electrode that is high-frequency traveling wave electrode configured to change carrier concentration in the modulation arm, and a second layer electrode that is a direct current electrode having an inductor function and comprises an inductor connected to the first layer electrode. ### Claim 2 (depends on 1) The electro-optic modulator according to claim 1, further comprising: a capacitor disposed on a side of the input waveguide and that is corresponding to each modulation arm; and wherein the electro-optic modulator has a modulator high-frequency signal input end, one end of the capacitor is connected to the modulator high-frequency signal input end, another end of the capacitor is connected to the high-frequency traveling wave electrode, and the capacitor and the inductor in the second layer electrode are both connected to the high-frequency traveling wave electrode and form a bias tee. ### Claim 3 (depends on 2) The electro-optic modulator according to claim 2, further comprises: a silicon substrate; a buried silicon dioxide layer disposed on the silicon substrate; a modulator active-area silicon waveguide and a silicon dioxide isolating layer that are disposed on the buried silicon dioxide layer; and wherein the second layer electrode is disposed on a side of the silicon dioxide isolating layer that is opposite to the buried silicon dioxide layer, the first layer electrode is buried in the silicon dioxide isolating layer, the first layer electrode and the second layer electrode are electrically connected, an electrode of the capacitor is disposed on the side of the silicon dioxide isolating layer that is opposite to the buried silicon dioxide layer, and another electrode of the capacitor is buried in the silicon dioxide isolating layer. ### Claim 4 (depends on 3) The electro-optic modulator according to claim 3, wherein the silicon dioxide isolating layer is disposed with a via hole, and the first layer electrode and the second layer electrode are connected by using metal filling the via hole. ### Claim 5 (depends on 1) The electro-optic modulator according to claim 1, further comprising: a thermal electrode loaded onto each branch of the beam combiner. ### Claim 6 (depends on 2) The electro-optic modulator according to claim 2, wherein the second layer electrode comprises: a modulator inductor corresponding to each modulation arm, and wherein one end of each modulator inductor is connected to a modulator direct-current signal input end and another end is connected to the high-frequency traveling wave electrode. ### Claim 7 (depends on 6) The electro-optic modulator according to claim 6, wherein the second layer electrode further comprises: a driver inductor corresponding to each modulation arm, and wherein one end of each driver inductor is connected to a driver direct-current signal input end and another end is connected to the modulator high-frequency signal input end of the electro-optic modulator. ### Claim 8 (depends on 3) The electro-optic modulator according to claim 3, wherein the second layer electrode comprises: a modulator inductor corresponding to each modulation arm, and wherein one end of each modulator inductor is connected to a modulator direct-current signal input end and another end is connected to the high-frequency traveling wave electrode. ### Claim 9 (depends on 8) The electro-optic modulator according to claim 8, wherein the second layer electrode further comprises: a driver inductor corresponding to each modulation arm, and wherein one end of each driver inductor is connected to a driver direct-current signal input end and another end is connected to the modulator high-frequency signal input end of the electro-optic modulator. ### Claim 10 (depends on 4) The electro-optic modulator according to claim 4, wherein the second layer electrode comprises: a modulator inductor corresponding to each modulation arm, and wherein one end of each modulator inductor is connected to a modulator direct-current signal input end and another end is connected to the high-frequency traveling wave electrode. ### Claim 11 (depends on 10) The electro-optic modulator according to claim 10, wherein the second layer electrode further comprises: a driver inductor corresponding to each modulation arm, and wherein one end of each driver inductor is connected to a driver direct-current signal input end and another end is connected to the modulator high-frequency signal input end of the electro-optic modulator.