Component carrier with bridge structure in through hole fulfilling minimum distance design rule

Patent metadata

Field	Value
Publication number	US-11546990-B2
Application number	US-202016751024-A
Country	US
Kind code	B2
Filing date	Jan 23, 2020
Priority date	Jan 31, 2019
Publication date	Jan 3, 2023
Grant date	Jan 3, 2023

Abstract

A component carrier with an electrically insulating layer structure has opposed main surfaces, a through-hole, and an electrically conductive bridge structure connecting opposing sidewalls delimiting the through-hole. The sidewalls have a first tapering portion extending from a first main surface and a second tapering portion extending from a second main surface. A first demarcation surface faces the first main surface and a second demarcation surface faces the second main surface. A central bridge plane extends parallel to the first main surface and the second main surface and is at a vertical center between a lowermost point of the first demarcation surface and an uppermost point of the second demarcation surface. A first intersection point is between the central bridge plane and one of the sidewalls delimiting the through hole. A length of a shortest distance from the first intersection point to the first demarcation surface is at least 8 μm.

First claim

The invention claimed is:

1. A component carrier, comprising:
an electrically insulating layer structure having a first main surface and a second main surface;
a through hole extending through the electrically insulating layer structure between the first main surface and the second main surface; and
an electrically conductive bridge structure connecting opposing sidewalls delimiting the through hole;
wherein the through hole has a first tapering portion extending from the first main surface and a second tapering portion extending from the second main surface;
wherein the electrically conductive bridge structure is delimited by a first demarcation surface facing towards the first main surface and by a second demarcation surface facing towards the second main surface and wherein the electrically conductive bridge structure only partially fills the through hole;
wherein a central bridge plane is defined to extend parallel to the first main surface and the second main surface and at a vertical center between a lowermost point of the first demarcation surface and an uppermost point of the second demarcation surface;
wherein a first intersection point is defined as a first intersection between the central bridge plane and one of the sidewalls delimiting the through hole;
wherein a length of a shortest distance from the first intersection point to the first demarcation surface is at least 8 μm;
wherein at least a part of the through hole has a central substantially cylindrical section between the first tapering portion and the second tapering portion,
wherein at least one of the central bridge plane and of the first intersection point is located at the central substantially cylindrical section of the through hole,
further comprising an electrically conductive layer structure on one of the first main surface and the second main surface of the electrically insulating layer structure, the electrically conductive layer structure with a lateral overhang extending into the through hole such that the bridge structure contacts opposed surfaces of the lateral overhang.

2. The component carrier according to claim 1 , wherein a length of a shortest distance from the first intersection point to the second demarcation surface is at least 8 μm.

3. The component carrier according to claim 1 , wherein a second intersection point is defined as a second intersection between the central bridge plane and another one of the sidewalk delimiting the through hole,
wherein a length of a shortest distance from the second intersection point to the first demarcation surface is at least 8 μm.

4. The component carrier according to claim 3 , wherein a length of a shortest distance from the second intersection point to the second demarcation surface is at least 8 μm.

5. The component carrier according to claim 1 , wherein a circumferential intersection line is defined by connecting all intersection points corresponding to an intersection between the central bridge plane and circumferential sidewalk delimiting the through hole;
wherein a length of all shortest distances from the circumferential intersection line to the first demarcation surface is at least 8 μm.

6. The component carrier according to claim 5 , wherein a length of all shortest distances from the circumferential intersection line to the second demarcation surface is at least 8 μm.

7. The component carrier according to claim 1 , comprising at least one of the following features:
a thickness of the electrically insulating layer structure is less than 100 μm;
the electrically insulating layer structure is a core;
the bridge structure also covers at least part of the sidewalls;
the bridge structure is composed of a seed layer being covered with a plating layer.

8. The component carrier according to claim 1 , further comprising:
a first electrically conductive bulk structure filling at least part of a volume between the first demarcation surface and the first main surface; and/or
a second electrically conductive bulk structure filling at least part of a volume between the second demarcation surface and the second main surface,
wherein at least one of the first demarcation surface and of the second demarcation surface is irregular on opposed sides of a line defined by a lower most point of the first demarcation surface and the uppermost point of the second demarcation surface, or
wherein the bridge structure is asymmetrical about the central bridge plane.

9. The component carrier according to claim 8 , wherein at least one of the first electrically conductive bulk structure and the second electrically conductive bulk structure is a plating structure.

10. The component carrier according to claim 1 , wherein at least one of a first electrically conductive layer structure on the first main surface and a second electrically conductive layer structure on the second main surface is a patterned electrically conductive layer structure.

11. The component carrier according to claim 1 , further comprising at least one of the following features:
at least one of the first demarcation surface and the second demarcation surface has a concave shape;
a cross-section of the bridge structure is substantially H-shaped;
a narrowest vertical thickness of the bridge structure is at least 20 μm;
a narrowest horizontal width of the through hole is not more than 100 μm;
a narrowest horizontal width of the through hole is not less than 30 μm;
a narrowest diameter of the through hole is in a range between 55 μm and 70 μm.

12. The component carrier according to claim 1 , further comprising at least one of the following features:
at least one component embedded in the component carrier, wherein the at least one component is selected from a group consisting of an electronic component, an electrically non-conductive and/or electrically conductive inlay, a heat transfer unit, a light guiding element, an energy harvesting unit, an active electronic component, a passive electronic component, an electronic chip, a storage device, a filter, an integrated circuit, a signal processing component, a power management component, an optoelectronic interface element, a voltage converter, a cryptographic component, a transmitter and/or receiver, an electromechanical transducer, an actuator, a microelectromechanical system, a microprocessor, a capacitor, a resistor, an inductance, an accumulator, a switch, a camera, an antenna, a magnetic element, a further component carrier, and a logic chip;
at least one electrically conductive layer structure of the component carrier includes at least one element of a group of elements consisting of copper, aluminum, nickel, silver, gold, palladium, and tungsten;
the electrically insulating layer structure comprises at least one of a group consisting of resin, reinforced or non-reinforced resin, epoxy resin or Bismaleimide-Triazine resin, FR-4, FR-5, cyanate ester, polyphenylene derivate, glass, prepreg material, polyimide, polyamide, liquid crystal polymer, epoxy-based build-up material, polytetrafluoroethylene, a ceramic, and a metal oxide;
the component carrier is shaped as a plate;
the component carrier is configured as one of a group consisting of a printed circuit board, and a substrate;
the component carrier is configured as a laminate-type component carrier.

13. A method of manufacturing a component carrier, the method comprising:
forming a through hole extending between a first main surface and a second main surface of an electrically insulating layer structure, wherein the through hole is formed with a first tapering portion extending from the first main surface, a second tapering portion extendin

Assignees

• At & S Austria Tech & Systemtechnik Ag

Inventors

• Tuominen Mikael

Classifications

• H05K2201/09563

  Metal filled via · CPC title

• H05K1/115 Primary

  Via connections; Lands around holes or via connections (H05K1/112 takes precedence) · CPC title

• H05K2201/09854

  Hole or via having special cross-section, e.g. elliptical · CPC title

• H05K1/09

  Use of materials for the {conductive, e.g. } metallic pattern · CPC title

• H05K3/4038

  Through-connections; Vertical interconnect access [VIA] connections (H05K3/403, H05K3/42 take precedence) · CPC title