Parallel optical interconnection module and method for manufacturing the same

• US 20040005119A1
• Filed: 10/04/2002
• Published: 01/08/2004
• Est. Priority Date: 06/07/2002
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Han, Sang-Pil, Kim, Byeong Cheol, Ahn, Seung Ho, Jeong, Myung Yung, Choi, Choon Gi, Cho, In Kui
• Granted Patent: US 6,912,332 B2
• Time in Patent Office: Days
• US Class Current: 385/49
• CPC Class Codes: G02B 6/42 Coupling light guides with opto-electronic elements
• CPC Class Codes: G02B 6/421 the intermediate optical component consisting of a short length of fibre, e.g. fibre stub
• CPC Class Codes: G02B 6/4214 the intermediate optical element having redirecting reflective means, e.g. mirrors, prisms for deflecting the radiation from horizontal to down- or upward direction toward a device G02B6/4246 takes precedence
• CPC Class Codes: H01L 2224/05554 being square
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/3011 Impedance

Abstract

The present invention relates to a parallel optical interconnection module for transmitting an optical signal over an optical fiber and receiving an optical signal from the optical fiber. According to the present invention, a reflection surface is formed at the end of the optical waveguide forming a core so that the path of light can be exactly changed and is focused. A light source/photodetector is buried within a trench using the silicon optical bench and an optical waveguide is manually aligned on the surface of the silicon optical bench, so that alignment error between the light source/photodetector and the optical waveguide can be minimized. A ferrule into which the optical waveguide is inserted is fixed to an adaptor so that alignment error between the optical waveguide and the light source/photodetector is minimized. Therefore, the present invention can minimize the coupling loss in the process during which the optical signal is transmitted to increase the optical output. Further, the present invention allows easy optical interconnection by means of a manual alignment and can increase the productivity.

Claims

1. A parallel optical interconnection module, comprising:

a substrate having a trench at a given region and a heat spreader and in which an electrode pad and given electronic circuit patterns are formed;

a silicon optical bench formed on the substrate and having a trench;

a light source/photodetector formed within the trench formed at the silicon optical bench and having a light source and a photodetector, wherein said light source generates an optical signal to output the signal toward the outside through an aperture and said photodetector receives the optical signal incident through the aperture from the outside and then converts the optical signal into an electrical signal;

a driving unit/receiving unit formed on the substrate and having a driver and a receiver, wherein said drive drives the light source depending on the electrical signal supplied through the electrode pad and said receiver amplifies the electrical signal from the photodetector to output the amplified signal to the electrode pad;

an optical waveguide having a core formed between lower and upper clad layers and having a reflection surface formed at the end of the core;

an adaptor connected to a connector connected to an optical fiber; and

a ferrule for fixing the optical waveguide to the adaptor,

wherein said substrate and said adaptor are coupled so that the aperture and the reflection surface are opposite.

2. The parallel optical interconnection module as claimed in claim 1, wherein said light source includes a vertical cavity surface emitting laser array.

3. The parallel optical interconnection module as claimed in claim 1, wherein said photodetector includes a photodiode array.

4. The parallel optical interconnection module as claimed in claim 1, wherein the reflection surface at one side of the optical waveguide is formed to be curved.

5. The parallel optical interconnection module as claimed in claim 1, wherein portions at the end of the reflection surface of a curved surface of the optical waveguide or the reflection of a plan surface is chamfered.

6. The parallel optical interconnection module as claimed in claim 1, wherein said lower and upper clad layers are made of either polymer or epoxy.

7. The parallel optical interconnection module as claimed in claim 1, wherein said core is are made of either polymer or epoxy.

8. The parallel optical interconnection module as claimed in claim 1, wherein said core has an uniform shape or a taper shape one side of which is widen than other one side.

9. The parallel optical interconnection module as claimed in claim 1, wherein a waveguide hole into which the optical waveguide is inserted, that is formed at the center of the ferrule, a guide hole into which a guide pin for interconnection with the adaptor, that is formed at both sides of the waveguide hole, and a fixing hole for fixing the optical waveguide, that is formed on the waveguide hole.

10. The parallel optical interconnection module as claimed in claim 9, wherein epoxy for fixing the optical waveguide is buried in the fixing hole.

11. The parallel optical interconnection module as claimed in claim 9, wherein said ferrule is made of a mixture of silica and polymer.

12. A method of manufacturing a parallel optical interconnection module, comprising the steps:

preparing an optical waveguide in which a core is formed between lower and upper clad layers and having a reflection surface at the end of the core;

forming a silicon nitride film pattern for defining a trench on said silicon optical bench;

etching the silicon optical bench using the silicon nitride film pattern as an etch mask to form a trench, wherein the trench is formed by controlling the marginal width and depth of the trench so that the light source/photodetector can be located at a desired location within the trench in a depth direction;

removing the silicon nitride film pattern;

depositing a base metal layer within the trench and performing annealing;

depositing a material for a solder within the trench and then heating the material to reflow the material;

inserting/mounting a light source/photodetector so that the light source/photodetector can be self-aligned in horizontal and depth directions within the trench; and

exactly aligning an alignment mask formed on the upper clad layer and an alignment mask formed on the silicon optical bench so that the reflection surface and the aperture formed at the light source/photodetector are opposite in order to attach the optical waveguide on the silicon optical bench.