US-12622280-B2 - Semiconductor device with through package via and method therefor

US12622280B2US 12622280 B2US12622280 B2US 12622280B2US-12622280-B2

Abstract

A method of forming a semiconductor device is provided. The method includes encapsulating with an encapsulant at least a portion of a semiconductor die and a package substrate, the encapsulant including an additive selectively activated by way of a laser. A first opening is formed in the encapsulant, the first opening exposing a predetermined first portion of the package substrate. The additive is activated at the sidewalls of the first opening. A second opening is formed in the encapsulant, the second opening encircling the first opening and exposing a predetermined second portion of the package substrate. The additive is activated at the sidewalls the second opening. A conductive material is plated on the additive activated portions of the encapsulant.

Inventors

Michael B. Vincent
Scott M. Hayes
Zhiwei Gong
Leo van Gemert
Antonius Hendrikus Jozef Kamphuis
Wen Hung HUANG

Assignees

NXP USA, INC.

Dates

Publication Date: 20260505
Application Date: 20220908

Claims (11)

1 . A semiconductor device comprising: a package substrate having a top surface; a semiconductor die coupled to the package substrate and having an active surface, a first die pad at the active surface, and a second die pad at the active surface, wherein the active surface faces away from the top surface of the package substrate; encapsulant covering at least a portion of the semiconductor die and at least a portion of the top surface of the package substrate, wherein the encapsulant has a top surface, the encapsulant including an additive selectively activated by way of a laser; a first opening through the encapsulant, wherein the first opening is defined by first sidewalls that extend from the top surface of the encapsulant to the active surface of the semiconductor die, and the first opening exposes the first die pad at the top surface of the semiconductor die; a vertical signal conductor within the first opening, wherein the vertical signal conductor has a first end coupled to the first die pad; a second opening through the encapsulant, wherein the second opening is defined by second sidewalls that extend from a top surface of the encapsulant to the top surface of the semiconductor die, the second opening at least partially surrounds the first opening but is separated from the first opening by a portion of the encapsulant, and the second opening exposes the second die pad at the top surface of the semiconductor die; and a shield conductor within the second opening, wherein the shield conductor at least partially surrounds the signal conductor but is separated from the signal conductor by the portion of the encapsulant, and the shield conductor has a first end coupled to the second die pad.
2 . The semiconductor device of claim 1 , further comprising a conductive radio frequency radiating element on a first surface of the encapsulant, wherein the conductive radio frequency radiating element extends perpendicular from and is electrically coupled to the signal element.
3 . The semiconductor device of claim 1 , wherein the encapsulant comprises: a first encapsulant covering the semiconductor die and the at least a portion of the top surface of the package substrate, wherein the second opening extends through the first encapsulant; and a second encapsulant within the first opening between the shield conductor and the signal conductor and overlying an upper surface of the first encapsulant, wherein the first opening extends through the second encapsulant.
4 . The semiconductor device of claim 3 , further comprising: a conductive shield on a surface of the first encapsulant, wherein the conductive shield is electrically coupled to the shield conductor; and a conductive radio frequency radiating element on a surface of the second encapsulant, wherein the conductive radio frequency radiating element is electrically coupled to the signal conductor, and the conductive radio frequency radiating element overlaps at least a portion of the conductive shield.
5 . The semiconductor device of claim 4 , wherein the package substrate further includes: a conductive trace at the top surface of the package substrate, wherein the conductive trace electrically couples the conductive shield and a connector at a bottom surface of the package substrate.
6 . A semiconductor device comprising: a package substrate having a top surface, a first trace at the top surface, and a second trace at the top surface; a semiconductor die coupled to the package substrate and having an active surface and a die pad at the active surface, wherein the active surface faces the top surface of the package substrate, and the die pad is electrically coupled to the first trace of the package substrate; encapsulant covering at least a portion of the semiconductor die and at least a portion of the top surface of the package substrate, wherein the encapsulant has a top surface, the encapsulant including an additive selectively activated by way of a laser; a first opening through the encapsulant, wherein the first opening is defined by first sidewalls that extend from the top surface of the encapsulant to the top surface of the package substrate, and the first opening exposes the first trace at the top surface of the package substrate; a vertical signal conductor within the first opening, wherein the vertical signal conductor has a first end coupled to the first trace; a second opening through the encapsulant, wherein the second opening is defined by second sidewalls that extend from a top surface of the encapsulant to the top surface of the package substrate, the second opening at least partially surrounds the first opening but is separated from the first opening by a portion of the encapsulant, and the second opening exposes the second trace at the top surface of the package substrate; and a shield conductor within the second opening, wherein the shield conductor at least partially surrounds the signal conductor but is separated from the signal conductor by the portion of the encapsulant, and the shield conductor has a first end coupled to the second trace.
7 . The semiconductor device of claim 6 , wherein the encapsulant comprises: a first encapsulant covering the semiconductor die and the at least a portion of the top surface of the package substrate, wherein the second opening extends through the first encapsulant; and a second encapsulant within the first opening between the shield conductor and the signal conductor and overlying an upper surface of the first encapsulant, wherein the first opening extends through the second encapsulant.
8 . The semiconductor device of claim 6 , wherein the encapsulant comprises: a first encapsulant covering the semiconductor die and the at least a portion of the top surface of the package substrate, wherein the first and second openings extend through the first encapsulant; a second encapsulant overlying an upper surface of the first encapsulant; and a third trace extending through the second encapsulant to contact the vertical signal conductor; and a conductive radio frequency radiating element on a surface of the second encapsulant, wherein the conductive radio frequency radiating element extends perpendicular from and is electrically coupled to the third trace.
9 . The semiconductor device of claim 6 , further comprising a conductive radio frequency radiating element on a first surface of the encapsulant, wherein the conductive radio frequency radiating element extends perpendicular from and is electrically coupled to the signal element.
10 . The semiconductor device of claim 9 , further comprising a conductive shield on a second surface of the encapsulant, wherein the conductive shield is electrically coupled to the shield conductor, and the conductive radio frequency radiating element overlaps at least a portion of the conductive shield.
11 . The semiconductor device of claim 6 , wherein the package substrate further includes: a third conductive trace that electrically couples the first trace of the package substrate and the die pad of the semiconductor die; and a fourth conductive trace that electrically couples the second trace of the package substrate and a connector at a bottom surface of the package substrate.

Description

BACKGROUND Field This disclosure relates generally to semiconductor device packaging, and more specifically, to semiconductor devices with a through package via and method of forming the same. Related Art Today, there is an increasing trend to include sophisticated semiconductor devices in products and systems that are used every day. These sophisticated semiconductor devices may include features for specific applications which may impact the configuration of the semiconductor device packages, for example. For some features and applications, the configuration of the semiconductor device packages may be susceptible to lower reliability, lower performance, and higher product or system costs. Accordingly, significant challenges exist in accommodating these features and applications while minimizing the impact on semiconductor devices' reliability, performance, and costs. BRIEF DESCRIPTION OF THE DRAWINGS The present invention is illustrated by way of example and is not limited by the accompanying figures, in which like references indicate similar elements. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. FIG. 1 through FIG. 6 illustrate, in simplified cross-sectional views, an example semiconductor device having a coaxial through package via (TPV) at stages of manufacture in accordance with an embodiment. FIG. 7 through FIG. 9 illustrate, in simplified cross-sectional views, the example semiconductor device at alternative stages of manufacture in accordance with an embodiment. FIG. 10 through FIG. 11 illustrate, in simplified cross-sectional views, alternative example semiconductor devices with a semiconductor die in an active-side-up orientation at a stage of manufacture in accordance with an embodiment. FIG. 12A and FIG. 12B through FIG. 14A and FIG. 14B illustrate, in simplified cross-sectional and corresponding plan views, example package substrate portions and semiconductor die portion of the example semiconductor devices at a stage of manufacture in accordance with embodiments. DETAILED DESCRIPTION Generally, there is provided, a semiconductor device with a coaxial through package via (TPV). The semiconductor device includes a semiconductor die and a package substrate at least partially encapsulated with an encapsulant. The encapsulant includes an additive capable of being activated by way of a laser in a laser direct structuring process. Openings are formed using laser ablation thus activating the encapsulant at the sidewalls of the openings. The openings are formed through the encapsulant such that predetermined conductive trace portions of the package substrate are exposed. The semiconductor device is subjected to a plating process which forms a plated signal conductor connected to a first trace in a first opening and a plated concentric shield conductor connected to a second trace in a second opening. The shield conductor is connected to a ground voltage supply terminal and surrounds the signal conductor to form the coaxial TPV connected to traces of the package substrate. By forming the semiconductor device with the coaxial TPV in this manner, low loss RF signal propagation can be realized with lower product costs. FIG. 1 illustrates, in a simplified cross-sectional view, an example semiconductor device 100 having a coaxial through package via (TPV) at a stage of manufacture in accordance with an embodiment. The term “through package via” or “TPV,” as used herein, generally refers to a vertical via formed through at least a portion of an encapsulant of the semiconductor device. At this stage of manufacture, the semiconductor device 100 includes a semiconductor die 102 and a package substrate 106 partially encapsulated with an encapsulant 124. In this embodiment, the encapsulant 124 is an epoxy molding compound which includes a chemical additive (e.g., copper chromate) capable of being activated by way of a laser in a laser direct structuring process. For example, when activated, a chemical reaction is initiated causing the activated portion of the encapsulant to form metal particles sufficient to serve as a seed layer for electroless plating (e.g., copper). The semiconductor die 102 has an active side (e.g., major side having circuitry) and a backside (e.g., major side opposite of the active side). The semiconductor die 102 includes die pads 104 formed at the active side. Die pads 104 may be configured for connection to respective signal conductor (formed at a subsequent stage) by way of the package substrate, for example. In this embodiment, semiconductor die 102 is configured in an active-side-down orientation with die pads 104 connected to conductive features of the package substrate 106. The term “conductive,” as used herein, generally refers to electrical conductivity unless otherwise specified. The semiconductor die 102 may be formed from any suitable semiconductor material, such as silicon, germanium, gallium arsenide, gallium ni