Three-dimensional multi-chips and tri-axial sensors and methods of manufacturing the same

• US 7,536,909 B2
• Filed: 01/20/2006
• Issued: 05/26/2009
• Est. Priority Date: 01/20/2006
• Status: Active Grant

• Current Assignee: Memsic Semiconductor (Wuxi) Co., Ltd. (MZ Investment Holdings Ltd.)
• Original Assignee: Memsic Incorporated (MZ Investment Holdings Ltd.)
• Inventors: Huang, Feiming, Zhao, Yang, Li, Zongya
• Primary Examiner(s): Kwok; Helen C.
• Application Number:
  US11/336,336
• Publication Number:
  US 20070170228A1
• Time in Patent Office: 1,222 Days
• Field of Search: 734/93, 735/10, 735/11, 734/31
• US Class Current: 73/493
• CPC Class Codes: B81B 7/0074 3D packaging, i.e. encapsulation containing one or several MEMS devices arranged in planes non-parallel to the mounting board
• CPC Class Codes: G01D 11/245 Housings for sensors
• CPC Class Codes: G01P 1/023 for acceleration measuring devices
• CPC Class Codes: G01P 15/18 in two or more dimensions
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/10253 Silicon [Si]

Abstract

Devices for providing tri-axial measurements in an x-direction, a y-direction, and a z-direction and methods of their manufacture are disclosed. The devices comprise a leadframe, at least one X- and Y-axis sensor die, at least one integrated circuit, and a Z-axis sensor. The Z-axis sensor is encapsulated in a pre-molding before the leadframe, X- and Y-axis sensor die(s), integrated circuit(s), and the pre-molding are encapsulated to provide a final molding.

Claims

1. A method of manufacturing a device for providing tri-axial measurements in an x-direction, a y-direction, and a z-direction, the method comprising the steps of:

providing a leadframe, a plurality of input/output leads, and a plurality of z-axis sensor leads;

attaching at least one X- and Y-axis sensor die, having orthogonal sensing directions, and at least one integrated circuit to be in at least one of physical communication and operational communication with the leadframe, the plurality of input/output leads, and the plurality of z-axis sensor leads;

attaching a z-axis sensor die, having a sensing direction, to at least two of the plurality of input/output leads and to at least two of the plurality of Z-axis sensor leads so that the sensing direction of said Z-axis sensor die is in the same or substantially the same plane as the orthogonal sensing directions of the at least one X- and Y-axis sensor die;

pre-encapsulating the Z-axis sensor die, some portion of the plurality of input/output leads, and some portion of the plurality of Z-axis sensor leads; and

re-positioning the pre-encapsulated Z-axis sensor die so that its sensing direction is orthogonal or substantially orthogonal to the orthogonal sensing directions of the at least one X- and Y-axis sensor die; and

encapsulating the leadframe, the plurality of input/output leads, the plurality of Z-axis sensor leads, the at least one X- and Y-axis sensor die, the at least one integrated circuit, and the pre-encapsulated Z-axis sensor die in a final molding.

2. The method as recited in claim 1, wherein the step of providing a leadframe comprises providing a leadframe that is structured and arranged with a vertical or substantially vertical portion.

3. The method as recited in claim 2, wherein the Z-axis sensor die is attached to the substantially vertical portion of the leadframe.

4. The method as recited in claim 3, wherein the Z-axis sensor die is attached to the substantially vertical portion by soldering, wire-bonding, flip-chip bonding or adhesively.

5. The method as recited in claim 1, wherein the step of providing a leadframe comprises providing a leadframe having a paddle portion and a plurality of leadframe legs.

6. The method as recited in claim 5, wherein the Z-axis sensor die is attached to the plurality of leadframe legs and the plurality of Z-axis sensor leads.

7. The method as recited in claim 3, wherein the Z-axis sensor die is attached to the substantially vertical portion by soldering, wire-bonding, flip-chip bonding or adhesively.

8. The method as recited in claim 1, wherein the step of attaching at least one X- and Y-axis sensor die and at least one integrated circuit includes attaching said at least one X- and Y-axis sensor die and said at least one integrated circuit to the leadframe, the plurality of input/output leads, and the plurality of Z-axis sensor leads by one or more of soldering, wire-bonding, flip-chip bonding and adhesively.

9. The method as recited in claim 1, wherein the method further comprises pre-encapsulating the Z-axis sensor die, some portion of the plurality of input/output leads, and some portion of the plurality of Z-axis sensor leads or pre-encapsulating the leadframe, some portion of said plurality of input/output leads, some portion of said plurality of Z-axis sensor leads, the at least one X- and Y-axis sensor die, and the at least one integrated circuit in a pre-molding prior to the encapsulating step.

10. The method as recited in claim 1, wherein the pre-encapsulated Z-axis sensor die is re-positioned by bending said pre-encapsulated Z-axis sensor die, said plurality of input/output leads, and said plurality of Z-axis sensor leads approximately 90 degrees from horizontal.