CN-122018093-A - Vertical coupling packaging structure and preparation method thereof

CN122018093ACN 122018093 ACN122018093 ACN 122018093ACN-122018093-A

Abstract

The invention provides a vertical coupling packaging structure and a preparation method thereof. The vertical coupling packaging structure comprises a heat sink, a detector chip, a radio frequency transmission line, a direct current adapter plate, a planar optical fiber and a planar optical fiber, wherein the heat sink comprises a first surface and a second surface which are perpendicular to each other, the detector chip is arranged on the first surface, a photosensitive surface is formed on the detector chip, the photosensitive surface is parallel to the first surface, the radio frequency transmission line is arranged on the first surface and is positioned on the first side of the detector chip, the radio frequency transmission line is electrically connected with the photosensitive surface, the direct current adapter plate is arranged on the first surface and is positioned on the second side of the detector chip, the second side is opposite to the first side, the direct current adapter plate is electrically connected with the photosensitive surface, and a light outlet of the planar optical fiber is arranged on the second surface and faces the photosensitive surface. The vertical coupling packaging structure not only can solve the problem of reduced responsiveness caused by low coupling efficiency, but also can ensure the signal integrity of the radio frequency signal, so that the radio frequency signal reaches an ideal bandwidth level.

Inventors

CHEN MAN
Shen Zheyuan
ZHAO ZEPING
LI LINYI
LIU JIANGUO

Assignees

中国科学院半导体研究所

Dates

Publication Date: 20260512
Application Date: 20241112

Claims (10)

1. A vertical coupling package structure, comprising: a heat sink including a first surface and a second surface perpendicular to each other; the detector chip is arranged on the first surface, and a photosensitive surface is formed on the detector chip and is parallel to the first surface; The radio frequency transmission line is arranged on the first surface and positioned on the first side of the detector chip, and is electrically connected with the photosensitive surface; The direct current adapter plate is arranged on the first surface and is positioned on the second side of the detector chip, the second side is opposite to the first side, and the direct current adapter plate is electrically connected with the photosensitive surface; the plane optical fiber is arranged on the second surface, and a light outlet of the plane optical fiber faces the photosensitive surface.
2. The vertical coupling package structure of claim 1, wherein a center of projection of the planar optical fiber at the first surface coincides with a center of the photosensitive surface.
3. The vertical coupling package structure of claim 1, wherein the long axis of the detector chip and the long axis of the radio frequency wire are both parallel to the second surface.
4. The vertical coupling package structure according to claim 1, wherein the direct current adapter plate is formed with a positive electrode portion and a ground electrode portion, the ground electrode portion is processed by a via hole, and the positive electrode portion is processed by side half-package metallization.
5. The vertical coupling package structure of claim 1, further comprising: The first capacitor is arranged on the first surface and located between the first side and the second side, the input end of the first capacitor is connected with the direct current adapter plate, the output end of the first capacitor is connected with the direct current bonding pad of the detector chip, and the first capacitor is used for carrying out filtering processing on voltage signals transmitted to the detector chip by the direct current adapter plate.
6. The vertical coupling package structure of claim 1, further comprising: And the second capacitor is coupled to the direct current adapter plate and is used for stabilizing the bias voltage generated by the direct current adapter plate.
7. The vertical coupling package structure of claim 1, further comprising: The metal tube shell comprises a first tube wall, a second tube wall and a third tube wall, wherein the first tube wall is parallel to the third tube wall, the second tube wall is vertically connected between the first tube wall and the third tube wall, the heat sink is arranged in a cavity surrounded by the first tube wall, the second tube wall and the third tube wall, and the first tube wall is opposite to the first surface.
8. The vertical coupling packaging structure according to claim 7, wherein a first through hole is formed in the first pipe wall, and a direct current pin is arranged in the first through hole and is connected with the input end of the direct current adapter plate through a gold wire; a second through hole is formed in the second pipe wall, and the planar optical fiber passes through the second through hole and is arranged on the second surface; And a third through hole is formed in the third pipe wall, a radio frequency feed-out part is arranged in the third through hole, and the radio frequency feed-out part is connected with the output end of the radio frequency transmission line.
9. A method for preparing the vertical coupling package structure according to any one of claims 1 to 8, comprising: A direct current adapter plate, a detector chip and a radio frequency transmission line are sequentially attached to the first surface of the heat sink, and the direct current adapter plate and the radio frequency transmission line are positioned on two opposite sides of the detector chip; the output end of the direct current adapter plate is electrically connected with the input end of the detector chip, and the output end of the detector chip is electrically connected with the output end of the radio frequency transmission line; and fixing the planar optical fiber on the second surface of the heat sink, so that the light outlet of the planar optical fiber faces the photosensitive surface of the detector chip, and the first surface and the second surface are perpendicular to each other.
10. The method of manufacturing of claim 9, wherein the securing the planar optical fiber to the second surface of the heat sink comprises: debugging the distance between the light outlet and the photosensitive surface to determine the target position of the planar optical fiber on the second surface; Fixing the planar optical fiber at the target position.

Description

Vertical coupling packaging structure and preparation method thereof Technical Field The invention relates to the field of photoelectric integrated device packaging, in particular to a vertical coupling packaging structure and a preparation method thereof. Background With the development of modern mobile internet, the information transmission quantity grows exponentially, and the electric interconnection shows limitation, so that the requirement of the information system for bandwidth and speed for mass data transmission is difficult to meet. Optical interconnection takes photons as an information transmission medium, and replaces electric interconnection gradually to become a mainstream technology of medium-long distance low-loss transmission by the advantage of low-loss high bandwidth. The complete optical interconnection communication system is composed of an optical transmitting end, an optical transmission link and an optical receiving end, wherein the photoelectric detector is a core device of the optical receiving end. The photoelectric detector is mainly divided into two device structures of surface incidence and waveguide coupling according to different light incidence modes, and is suitable for different application scenes. The silicon-based germanium photoelectric detector with the waveguide structure is easy to integrate with other optical waveguide devices, and is suitable for on-chip optical interconnection and other applications. The surface incidence structure is optically coupled with simple and high efficiency, is flexible to use, and is suitable for optical communication, optical interconnection, optical sensing optical receiving modules and the like. The optical coupling design is a very critical step in the packaging process of the optical receiving module, and the coupling efficiency directly influences the characteristics of device responsivity, system sensitivity and the like. Therefore, how to improve the coupling efficiency while ensuring the bandwidth level is an important issue in the art. Disclosure of Invention In view of this, the invention provides a vertical coupling packaging structure and a preparation method thereof, so as to solve the problem that the bandwidth and the responsivity of the broadband surface incident photoelectric detector chip after packaging cannot be simultaneously considered. The invention provides a vertical coupling packaging structure which comprises a heat sink, a detector chip, a radio frequency transmission line, a direct current adapter plate, a planar optical fiber and a planar optical fiber, wherein the heat sink comprises a first surface and a second surface which are mutually perpendicular, the detector chip is arranged on the first surface, a photosensitive surface is formed on the detector chip, the photosensitive surface is parallel to the first surface, the radio frequency transmission line is arranged on the first surface and is positioned on a first side of the detector chip, the radio frequency transmission line is electrically connected with the photosensitive surface, the direct current adapter plate is arranged on the first surface and is positioned on a second side of the detector chip, the second side is opposite to the first side, the direct current adapter plate is electrically connected with the photosensitive surface, and a light outlet of the planar optical fiber is arranged on the second surface and faces the photosensitive surface. According to the embodiment of the invention, the projection center of the planar optical fiber on the first surface coincides with the center of the photosensitive surface. According to an embodiment of the invention, the long axis of the detector chip and the long axis of the radio frequency line are both parallel to the second surface. According to the embodiment of the invention, the direct current adapter plate is provided with the positive electrode part and the ground electrode part, the ground electrode part is processed by a via hole, and the positive electrode part is processed by side half-package metallization. According to the embodiment of the invention, the vertical coupling packaging structure further comprises a first capacitor, wherein the first capacitor is arranged on the first surface and is positioned between the first side and the second side, the input end of the first capacitor is connected with the direct current adapter plate, the output end of the first capacitor is connected with the direct current bonding pad of the detector chip, and the first capacitor is used for filtering a voltage signal transmitted to the detector chip by the direct current adapter plate. According to the embodiment of the invention, the vertical coupling packaging structure further comprises a second capacitor, wherein the second capacitor is coupled to the direct current adapter plate and used for stabilizing bias voltage generated by the direct current adapter plate. According to the embodi