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KR-20260063141-A - SURFACE ACOUSTIC WAVE FILTER PACKAGE AND FABRICATING METHOD OF THE SAME

KR20260063141AKR 20260063141 AKR20260063141 AKR 20260063141AKR-20260063141-A

Abstract

A SAW filter package and a method for manufacturing the same are provided. The SAW filter package comprises: a first substrate on which a Surface Acoustic Wave (SAW) filter is formed; an electrode pad layer formed on the first substrate; an Under Bump Metallurgy (UBM) layer formed on the electrode pad; a second substrate; and a metal bump electrically connecting the first substrate and the second substrate, wherein the UBM layer comprises an aluminum and copper alloy, and the metal bump comprises a gold and palladium alloy.

Inventors

  • 조준오
  • 장영훈
  • 곽우영
  • 김창덕

Assignees

  • (주)와이솔

Dates

Publication Date
20260507
Application Date
20241030

Claims (12)

  1. A first substrate having a SAW (Surface Acoustic Wave) filter formed thereon; An electrode pad layer formed on the first substrate; A UBM (Under Bump Metallurgy) layer formed on the electrode pad above; Second substrate; and It includes a metal bump that electrically connects the first substrate and the second substrate, The above UBM layer comprises aluminum and copper alloys, and The above metal bump comprises a gold and palladium alloy, SAW filter package.
  2. In Article 1, The copper content relative to the total mass of the above UBM layer is 0.5% to 2%, SAW filter package.
  3. In Paragraph 2, The bonding strength by the above UBM layer is 600g or more, SAW filter package.
  4. In Article 1, The palladium content relative to the total mass of the above metal bump is 1% or more, SAW filter package.
  5. In Article 1, An IMC (Intermetallic Compound) is formed between the metal bump and the UBM layer, and A palladium-rich layer is formed between the above IMC and the above metal bump. SAW filter package.
  6. In Paragraph 5, Kirkendall voids formed in the above IMC are not diffused into the metal bump by the palladium-rich layer, SAW filter package.
  7. A step of sequentially forming an electrode pad layer and a UBM layer on a first substrate on which a SAW filter is formed; A step of forming a metal bump on the above UBM layer; and The method includes the step of bonding the second substrate and the first substrate via the metal bump, The above UBM layer comprises aluminum and copper alloys, and The above metal bump comprises a gold and palladium alloy, Method for manufacturing a SAW filter package.
  8. In Article 7, The copper content relative to the total mass of the above UBM layer is 0.5% to 2%, Method for manufacturing a SAW filter package.
  9. In Article 7, The palladium content relative to the total mass of the above metal bump is 1% or more, Method for manufacturing a SAW filter package.
  10. In Article 7, The step of bonding the second substrate and the first substrate via the metal bump is A step comprising performing annealing on the metal bump above, Method for manufacturing a SAW filter package.
  11. In Article 10, The step of forming metal bumps on the above UBM layer is, The method includes the step of forming an IMC layer between the above UBM layer and the above metal bump, The step of performing annealing on the above metal bump is, A step comprising growing the above IMC layer, Method for manufacturing a SAW filter package.
  12. In Paragraph 11, Kirkendall voids formed in the IMC are not diffused into the metal bump by the palladium-rich layer formed between the IMC and the metal bump. Method for manufacturing a SAW filter package.

Description

SAW filter package and method of manufacturing the same The present invention relates to a SAW filter package and a method for manufacturing the same, and more specifically, to a SAW filter package and a method for manufacturing the same in which the possibility of void defects occurring is reduced by including a metal bump and an Under Bump Metallurgy (UBM) layer with improved reliability. Since forming solder or gold bumps on aluminum pads formed on semiconductor chips results in poor adhesion, UBM (Under Bump Metallurgy) is additionally formed to act as an intermediary between the bumps and the pads, thereby reinforcing the bonding strength. These UBM devices form a connection structure by, for example, forming a gold UBM layer on an aluminum electrode formed with a titanium (Ti) layer, and forming gold UBM and gold bumps. However, since gold, a precious metal, increases manufacturing costs during the mass production of SAW filter packages, research is ongoing on connection structures that can guarantee the same performance, such as bonding performance and reliability, while reducing the amount of gold included. FIG. 1 is a drawing for illustrating a SAW filter package according to an embodiment of the present invention. FIG. 2 is a diagram illustrating the connection structure of a first substrate and a second substrate included in a SAW filter package according to an embodiment of the present invention. Figure 3 is a diagram illustrating the IMC formed in the connection structure of Figure 2. Figures 4a and 4b are SEM images of the IMC of Figure 3. Figures 5a and 5b are SEM images illustrating the degree of void formation according to the palladium ratio of the metal bumps. FIG. 6 is a diagram illustrating the bonding strength according to the aluminum alloy ratio of the UBM layer included in a SAW filter package according to an embodiment of the present invention. FIGS. 7 and 8 are intermediate step drawings for explaining a method for manufacturing a SAW filter package according to an embodiment of the present invention. Figures 9a and 9b are SEM images illustrating the IMC formed during the manufacturing process of a SAW filter package according to an embodiment of the present invention. The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same components. When one component is referred to as being "connected to" or "coupled to" another component, it includes cases where it is directly connected or coupled to the other component, or cases where another component is interposed. Conversely, when one component is referred to as being "directly connected to" or "directly coupled to" another component, it indicates that no other component is interposed. "And/or" includes each of the mentioned items and all combinations of one or more of them. The terms used herein are for describing the embodiments and are not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise in the text. As used herein, "comprises" and/or "comprising" do not exclude the presence or addition of one or more other components, steps, actions, and/or elements to the mentioned components, steps, actions, and/or elements. Although terms such as "first," "second," etc., are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used merely to distinguish one component from another. Therefore, it goes without saying that the "first component" mentioned below may be the "second component" within the technical scope of the present invention. Unless otherwise defined, all terms used in this specification (including technical and scientific terms) may be used in a meaning commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless explicitly and specifically defined otherwise. FIG. 1 is a drawing for illustrating a SAW filter package according to an embodiment of the present invention. Referring to FIG. 1, a SAW filter package according to an embodiment of the present invention may include a first substrate (100) and a second substrate (200), etc. The first substrate (100) may be a substrate on which a Surface Acoustic Wave (SAW) filter is formed. The first