APPARATUS AND METHOD FOR USE IN MOUNTING ELECTRONIC ELEMENTS

• US 20070252250A1
• Filed: 04/26/2006
• Published: 11/01/2007
• Est. Priority Date: 04/26/2006
• Status: Active Grant

• Current Assignee: Creeled Incorporated
• Original Assignee: Cotco Holdings Limited
• Inventors: Hui, Xie, Cheong, Cheng
• Granted Patent: US 7,635,915 B2
• Time in Patent Office: Days
• US Class Current: 257/672
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H01L 33/642 characterized by the shape
• CPC Class Codes: H01L 33/647 the elements conducting electric current to or from the semiconductor body

Abstract

Some embodiments provide surface mount devices that include a first electrode comprising a chip carrier part, a second electrode disposed proximate to the chip carrier part, and a casing encasing a portion of the first and second electrodes. The first electrode can extend from the chip carrier part toward a perimeter of the casing, and the second electrode can extend away from the chip carrier part and projects outside of the casing. In extending away from the chip carrier part the first electrode divides into a plurality of leads separated by an aperture that join into a single first joined lead portion with a first width before projecting outside of the casing and maintains the first width outside of the casing. The second electrode can attain a second width prior to projecting outside of the casing and maintains the second width outside the casing.

Claims

1. A surface mount device, comprising:

a first electrode comprising a chip carrier part;

a second electrode disposed proximate to the chip carrier part and separated from the chip carrier part by an insulation gap; and

a casing encasing a portion of the first electrode and a portion of the second electrode, and the casing having a recess extending from a first surface of the casing into the casing such that at least a portion of the chip carrier part is exposed through the recess;

the first electrode extends from the chip carrier part toward a perimeter of the casing, divides into a first plurality of leads separated by an aperture as the first electrode extends from the chip carrier part toward the perimeter of the casing, the first plurality of leads join into a single first joined lead portion having a first width before the first electrode projects outside of the casing and the first electrode projects outside the casing as the first electrode maintains the first width outside of the casing; and

the second electrode extends away from the chip carrier part, attains a second width prior to projecting outside of the casing, and projects outside of the casing maintaining the second width outside of the casing.

2. The device of claim 1, wherein the first electrode is positioned relative to the casing such that the portion of the chip carrier part and a first portion of the aperture extend into a perimeter of the recess and are exposed through the recess.

3. The device of claim 2, wherein casing material forming the casing extends through a second portion of the aperture that is not exposed through the recess.

4. The device of claim 3, further comprising:

a fill material disposed within at least a portion of the recess where at least a portion of the fill material extends into the first portion of the aperture.

5. The device of claim 4, wherein the second electrode comprises a second plurality of leads separated by an inlet and positioned relative to the casing such that a portion of each of the second plurality of leads and a first portion of the inlet extend into the perimeter of the recess and are exposed through the recess;

at least a portion of the fill material extends into the first portion of the inlet; and

casing material extends through a second portion of the inlet not exposed by the recess.

6. The device of claim 1 wherein the first electrode widens as it extends from the chip carrier part toward the perimeter of the casing, narrows as it splits into the first plurality of leads, and widens as the first plurality of leads join into the first joined lead portion to the first width before the first electrode projects outside of the casing.

8. The device of claim 1, wherein the second electrode comprises a second plurality of leads each having a head end positioned juxtaposed to the chip carrier part where an edge of each of the head ends of the second plurality of leads parallel edges of the chip carrier part, and a portion of the chip carrier part extends between the head ends of the second plurality of leads.

9. The device of claim 8, wherein the second plurality of leads join into a second joined lead portion with the second electrode widening as the second plurality of leads join into the second joined lead portion before the second electrode projects outside of the casing such that the second joined lead portion extends through a second surface of the casing.

10. The device of claim 1, wherein the insulation gap between adjacent portions of the first electrode and the second electrode is formed by edges of the second electrode paralleling edges of chip carrier part of the first electrode.

7. The device of claim 7, further comprising:

a first indentation along a first edge of the first electrode defined by the widening of the chip carrier part, the narrowing of the plurality of leads and the widening of the first joined lead portion; and

a second indentation along a second edge of the first electrode defined by the widening of the chip carrier part, the narrowing of the plurality of leads and the widening of the first joined lead portion.

11. A surface mount device, comprising:

a first electrode comprising a chip carrier part and a plurality of leads extending away from the chip carrier part with first and second leads extending generally in parallel and in a first direction away from the chip carrier part and a third lead extending away from the chip carrier part in a second direction substantially opposite the first direction;

a second electrode positioned proximate the chip carrier part and extending away from the chip carrier part;

an insulation gap separating the second electrode from the first electrode; and

a casing that encases portions of the first and second electrodes and where the plurality of leads of the first electrode and the second electrode protrude through surfaces of the casing, and the casing comprising a recess formed in the casing such that a portion of the chip carrier part is exposed through the recess.

12. The device of claim 11, wherein the first and second leads of the first electrode are separated by a first lead gap, and the third lead and the second electrode are separated by a second lead gap, and the first and second electrodes are positioned relative to the casing such that the portion of the chip carrier part, a portion of the isolation gap, a portion of the first lead gap and a portion of the second lead gap extend into the recess and are exposed through the recess.

13. The device of claim 12, wherein the chip carrier part further comprises an extension portion and an extension indentation formed in the extension portion such that a portion of the extension indentation extends into the perimeter of the recess and is exposed through the recess.

14. The device of claim 13, further comprising:

a fill material filling at least a portion of the recess and extending into the portion of the insulation gap, the portion of the first lead gap, the portion of the second lead gap and the portion of the extension indentation that are exposed through the recess.

15. A surface mount device, comprising:

a first electrode comprising a chip carrier part;

a second electrode disposed at a distance from the chip carrier part; and

a casing encasing a portion of the first electrode and a portion of the second electrode, and the casing having a recess extending from a surface of the casing into the casing such that at least a portion of the chip carrier part is exposed through the recess;

the first electrode extends from the chip carrier part toward a perimeter of the casing and projects outside of the casing, and wherein the second electrode projects outside of the casing;

the first electrode is generally trapezoidal-shaped at the chip carrier part, the first electrode comprises a plurality of leads as the first electrode extends from the chip carrier part toward the perimeter of the casing, the plurality of leads having predefined widths before the plurality of leads project outside of the casing and maintaining the predefined widths outside of the casing, and the second lead attaining an additional predefined width prior to projecting outside the casing and maintaining the additional predefined width outside of the casing.

16. The device of claim 15, wherein the first electrode and the second electrode in combination are generally H-shaped.

17. The device of claim 15, wherein the first electrode narrows as it extends into the first and second leads, the first and second leads widening to first and second widths of the predefined widths, respectively, prior to the first and second leads projecting outside of the casing, and first and second leads maintain the first and second widths, respectively, outside the casing.

18. The device of claim 17, further comprising:

a first indentation along a first edge of the first electrode defined by the narrowing of the first electrode extending into the first lead and the first lead widening to the first width prior to projecting outside the casing, and a second indentation along a second edge of the first electrode defined by the narrowing of the first electrode extending into the second lead and the second lead widening to the second width prior to projecting outside the casing.

19. The device of claim 15, wherein the second electrode narrows as it extends away from the chip carrier part and widens to the additional predefined width before the second electrode projects outside of the casing defining an indentation along a first edge of the second electrode.