JP-7856833-B1 - Optical module

Abstract

[Problem] To improve the heat dissipation of the optical integrated circuit in an optical module having an electrical integrated circuit and an optical integrated circuit. [Solution] The optical module comprises a wiring board having a core layer, a first laminate stacked on the upper surface of the core layer, recesses opening on the upper and side surfaces of the first laminate, and a first metal layer disposed on the upper surface of the core layer with its upper surface exposed at the bottom of the recess; an optical integrated circuit disposed on the upper surface of the first metal layer; and an electrical integrated circuit disposed on the upper surface of the first laminate, capable of transmitting and receiving signals with the optical integrated circuit, wherein the first metal layer extends from a region overlapping with the optical integrated circuit in a plan view to a region not overlapping with the optical integrated circuit in a plan view. [Selection Diagram] Figure 2

Inventors

• 傳田 達明

Assignees

• 新光電気工業株式会社

Dates

Publication Date

20260511

Application Date

20250807

Claims (10)

1. A wiring board having a core layer, a first laminate laminated on the upper surface of the core layer, recesses opening on the upper and side surfaces of the first laminate, and a first metal layer disposed on the upper surface of the core layer with its upper surface exposed at the bottom of the recess, An optical integrated circuit having a pad and disposed on the upper surface of the first metal layer, The first laminate is disposed on the upper surface and includes an electrical integrated circuit capable of transmitting and receiving signals with the optical integrated circuit, The optical integrated circuit is positioned with the side opposite to the side on which the pad is provided facing the first metal layer, The first metal layer extends from a region overlapping with the optical integrated circuit in a plan view to a region not overlapping with the optical integrated circuit in a plan view, forming an optical module.
2. The wiring board further comprises a second laminate stacked on the lower surface of the core layer, The second laminate has a second metal layer disposed on the lower surface of the core layer, The second metal layer is electrically connected to the first metal layer via through-wiring that penetrates the core layer. The optical module according to claim 1, wherein the second metal layer extends from a region that overlaps with the optical integrated circuit in a plan view to a region that does not overlap with the optical integrated circuit in a plan view.
3. The second laminate has a plurality of third metal layers arranged alternately with an insulating layer in between in the layer below the second metal layer. Each of the plurality of third metal layers is electrically connected to the second metal layer via via wiring that penetrates the insulating layer. The optical module according to claim 2, wherein each of the plurality of third metal layers extends from a region that overlaps with the optical integrated circuit in a plan view to a region that does not overlap with the optical integrated circuit in a plan view.
4. A plurality of optical integrated circuits are arranged spaced apart from each other on the upper surface of one of the first metal layers, The first laminate comprises a plurality of electrical integrated circuits arranged spaced apart from each other on the upper surface of the first laminate, The optical module according to claim 1, wherein one electrical integrated circuit capable of transmitting and receiving signals is connected to each of the optical integrated circuits.
5. The optical module according to claim 1, wherein the side surface of the core layer has an optical component capable of transmitting and receiving optical signals with the optical integrated circuit.
6. The optical integrated circuit has a first optical waveguide, The optical module according to claim 5, wherein the optical integrated circuit is capable of transmitting and receiving optical signals with the optical component via a second optical waveguide.
7. The second optical waveguide has a plurality of cores, The optical module according to claim 6, wherein the plurality of cores have a fan-out structure in which the pitch of the connection portion with the optical component is wider than the pitch of the connection portion with the first optical waveguide.
8. The optical integrated circuit is arranged on the upper surface of the first metal layer such that the first optical waveguide is located on the side furthest from the electrical integrated circuit. The optical module according to claim 6, wherein the second optical waveguide is located on the upper surface of the core layer.
9. The optical integrated circuit is arranged on the upper surface of the first metal layer such that the first optical waveguide is located on the side closer to the electrical integrated circuit. The optical module according to claim 6, wherein the second optical waveguide is disposed on the upper surface of the core layer via a glass spacer.
10. The optical module according to any one of claims 1 to 9, wherein the core layer is made of glass.

Description

This invention relates to an optical module. A photoelectric conversion device is known that comprises a circuit board having a first recess, a first metal wiring formed on the circuit board from the bottom surface of the first recess to the surface where the first recess is formed, an optical element disposed within the first recess and flip-chip bonded to the first metal wiring at the bottom surface of the first recess, and a circuit chip flip-chip bonded to the first metal wiring on the surface where the first recess is formed (Patent Document 1). Japanese Patent Publication No. 2010-16012 This is a plan view illustrating an optical module according to the first embodiment.This is a partial plan view illustrating an optical module according to the first embodiment.This is a partial cross-sectional view illustrating an optical module according to the first embodiment.This is a diagram (part 1) illustrating the manufacturing process of an optical module according to the first embodiment.This is a diagram (part 2) illustrating the manufacturing process of an optical module according to the first embodiment.This is a partial plan view illustrating an optical module according to a modified example 1 of the first embodiment.This is a partial cross-sectional view illustrating an optical module according to a modified example 1 of the first embodiment.This is a partial cross-sectional view illustrating an optical module according to a modified example 2 of the first embodiment.This is a plan view illustrating an optical module according to a modified example 3 of the first embodiment. The following describes embodiments for carrying out the invention with reference to the drawings. Note that in each drawing, identical components are denoted by the same reference numerals, and redundant explanations may be omitted. <First Embodiment> [Structure of the optical module] Figure 1 is a plan view illustrating an optical module according to the first embodiment. Figure 2 is a partial plan view illustrating an optical module according to the first embodiment, showing an enlarged view of the R portion of Figure 1. Figure 3 is a partial cross-sectional view illustrating an optical module according to the first embodiment, showing a cross-section along the line A-A in Figure 2. Referring to Figures 1 to 3, the optical module 1 includes a wiring board 2, a photonic integrated circuit (PIC) 60, an electronic integrated circuit (EIC) 70, an electronic integrated circuit 80, and an optical fiber array 90. The electrical integrated circuit 80 can, for example, be positioned near the center of the wiring board 2 in a plan view. The optical integrated circuit 60, the electrical integrated circuit 70, and the optical fiber array 90 can each be positioned one or more times. If the wiring board 2 is rectangular in a plan view, the optical integrated circuit 60, the electrical integrated circuit 70, and the optical fiber array 90 may be positioned in multiple sets, for example, along each side of the rectangle. In this case, since the electrical integrated circuit 80 and each electrical integrated circuit 70 can be positioned close together, high-speed transmission and reception of electrical signals between the electrical integrated circuit 80 and each electrical integrated circuit 70 becomes possible. (Wiring board 2) The wiring board 2 has a core layer 10 having an upper surface 10a and a lower surface 10b which is the opposite surface of the upper surface 10a; a first laminate 51 including wiring layers and insulating layers alternately stacked on the upper surface 10a of the core layer 10; a second laminate 52 including wiring layers and insulating layers alternately stacked on the lower surface 10b of the core layer 10; and recesses 51x that open on the upper surface and side surface of the first laminate 51. The first laminate 51 has, sequentially laminated on the upper surface 10a of the core layer 10, a wiring layer 12, an insulating layer 13, a wiring layer 14, an insulating layer 15, a wiring layer 16, an insulating layer 17, a wiring layer 18, an insulating layer 19, a wiring layer 20, an insulating layer 21, a wiring layer 22, an insulating layer 23, a wiring layer 24, and a solder resist layer 25. The second laminate 52 has, sequentially laminated on the lower surface 10b of the core layer 10, a wiring layer 32, an insulating layer 33, a wiring layer 34, an insulating layer 35, a wiring layer 36, an insulating layer 37, a wiring layer 38, an insulating layer 39, a wiring layer 40, an insulating layer 41, a wiring layer 42, an insulating layer 43, a wiring layer 44, and a solder resist layer 45. In the first embodiment, for convenience, the solder resist layer 25 side of the wiring board 2 of the optical module 1 is referred to as the upper side or one side, and the solder resist layer 45 side as the lower side or the other side. Furthermore, the surface of each portion facing the solder resist layer 25 is referred to as