DAM LAMINATE ISOLATION SUBSTRATE
An apparatus includes a lead frame, a dam and adhesive on portions of the lead frame, and an integrated circuit die having a portion on the dam and another portion on the adhesive. The lead frame can include two portions, or two lead frames. The dam can bridge a space between the two lead frames. The dam can be smaller than the integrated circuit die in at least a width dimension of the dam relative to a width dimension of the integrated circuit die, providing that the integrated circuit die overhangs the dam on each side of the width dimension of the dam. Adhesive is located between the integrated circuit die and each lead frame, adjacent to and on each side of the dam. The dam prevents adhesive from spreading into the space between the lead frames.
This application is a continuation of U.S. patent application Ser. No. 15/852,532, filed Dec. 22, 2017, the contents of all of which are herein incorporated by reference in it entirety.
BACKGROUNDSemiconductor packages often comprise a semiconductor die attached to a lead frame and electrically connected to bond fingers of the lead frame. The semiconductor die is attached to the lead frame by an adhesive resin. Adhesive resins for attaching the semiconductor die to the lead frame include epoxy-based adhesives, acrylate-based adhesives, silicones and polyimides.
Although such adhesives are fairly viscous, they exhibit a tendency to bleed or spread into a space between lead frames of the substrate, possibly causing bridging and/or arcing. This spreading or bleeding of adhesive resin into the space between lead frames of the substrate encroaches upon the HV-LV split DAP spacing and effects proper clearances of M4/5/6 trace-DAP.
There exists a continuing need for a reliable and simple basis for solving the adhesive resin bleed problem that causes damage to, short circuiting of, or poor isolation performance of, the semiconductor package.
SUMMARYIn one aspect, an apparatus includes a lead frame, a dam and adhesive on portions of the lead frame, and an integrated circuit die having a portion on the dam and another portion on the adhesive. The lead frame can include two portions, or two lead frames. The dam bridges a space between the two lead frames. The dam can be smaller than the integrated circuit die in at least a width dimension of the dam relative to a width dimension of the integrated circuit die, providing that the integrated circuit die overhangs the dam on each side of the width dimension of the dam. Adhesive is located between the integrated circuit die and each lead frame, adjacent to and on each side of the dam. The dam prevents adhesive from spreading into the space between the lead frames. The dam can be a dry film, for example, a PSR800 AUS410 dry film.
In another aspect, an apparatus includes a lead frame, a dam and adhesive on portions of the lead frame, and an integrated circuit die having a portion on the dam and another portion on the adhesive. In this aspect, the dam is smaller than the integrated circuit die in a width and length dimension of the dam relative to the integrated circuit die, over at least a portion of the dam and the integrated circuit die, where the integrated circuit die overhangs the dam in each location where the dam is smaller than the integrated circuit die in the width or the length dimension. The dam and the integrated circuit die bridge a space adjacent to a side of the lead frame. Adhesive is located between the integrated circuit die and the lead frame, adjacent to and on each side of the dam, due to the dam being smaller than the integrated circuit die in the width and the length dimension. The dam prevents adhesive from spreading into the space adjacent to the side of the lead frame.
In a further aspect, a method of manufacturing an integrated circuit package includes the steps of placing an integrated circuit die on a dam, the dam being smaller than the integrated circuit die in at least a width dimension of the dam relative to a width dimension of the integrated circuit die, where the integrated circuit die overhangs the dam on each side of the width dimension of the dam. The integrated circuit die and the dam are placed on a two portion lead frame, where the dam and the integrated circuit die bridge a space between the two portions of the lead frame. Adhesive is located between the integrated circuit die and the lead frame, adjacent to and on each side of the dam, due to the dam being smaller than the integrated circuit die in at least the width dimension. The dam prevents the adhesive from spreading into the space between the two portions of the lead frame. The dam can be attached to the integrated circuit die prior to the placing of the integrated circuit die and the dam on the two portions of lead frame. In this aspect, manufacturing the integrated circuit package could include connecting bond pads of the integrated circuit die to bond finger connections of the integrated circuit package, and encapsulating the integrated circuit die in the integrated circuit package.
For a detailed description of various examples, reference will now be made to the accompanying drawings in which:
Certain terms are used throughout the following description and claims to refer to particular system components. As one skilled in the art will appreciate, different parties may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .”
The bond fingers 116 generally extend about a perimeter of a side surface of the die 114 attached to the lead frame 112. The bond fingers 116 are electrically connected to the bond pads 118 on a surface of the die 114 by respective bond wires 120.
The lead frame 112 can include two portions or sides 122, 124, or two lead frames 122, 124 (e.g., a high voltage (HV) side 122 and a low voltage (LV) side 124). In the cross-section view of
The integrated circuit die 114 is attached to the lead frame 112 by an adhesive resin 130. As shown in
As shown in
As shown in
In one aspect, the dam 350 lies within the inside of the die 114 area. In another aspect, the dam 350 is smaller than the integrated circuit die 114 in at least a width dimension of the dam 350 and of the integrated circuit die 114. In a further aspect, the integrated circuit die 114 overhangs the dam on each side of the width dimension of the dam 350 and of the integrated circuit die 114, when the dam 350 is attached to, or is arranged relative to, the die 114. As shown in
The above discussion is meant to be illustrative of the principles and various examples of the disclosure. Numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications.
Claims
1. An apparatus, comprising:
- a first portion of a lead frame, and a second portion of a lead frame, the first portion of the lead frame and the second portion of the lead frame electrically connected to at least a first lead and a second lead of a plurality of leads respectively;
- a component bridging a space between the first portion of the lead frame and the second portion of the lead frame; and
- an integrated circuit die having a portion on the component.
2. The apparatus of claim 1, further comprising an adhesive in contact with the component, the integrated circuit die and the first portion of the lead frame and the second portion of the lead frame.
3. The apparatus of claim 1, wherein the component is a dry film.
4. The apparatus of claim 1, wherein the component is a solder resist.
5. The apparatus of claim 1, wherein the component is a PSR800 AUS410 film.
6. The apparatus of claim 1, wherein the component is generally between 25 and 30 microns in thickness from a side view of the apparatus.
7. The apparatus of claim 1, wherein the component generally has a T shape from a top view of the apparatus.
8. The apparatus of claim 1, wherein an area of the component is less than an area of the integrated circuit die, from a top view of the apparatus.
9. The apparatus of claim 1, wherein the integrated circuit die overhangs the component on each side of a width dimension of the component.
10. The apparatus of claim 1, wherein the integrated circuit die is electrically connected to at least one of the plurality of leads.
11. The apparatus of claim 10, wherein the first portion of the lead frame and the second portion of the lead frame are electrically isolated from each other.
12. The apparatus of claim 1, wherein the first portion of the lead frame operates at a voltage higher than an operating voltage of the second portion of the lead frame.
13. The apparatus of claim 10, wherein the first portion of the lead frame is a first die attach pad and the second portion of the lead frame is a second die attach pad.
14. An apparatus, comprising:
- a first portion of a lead frame, and a second portion of a lead frame, the first portion of the lead frame and the second portion of the lead frame electrically connected to at least a first lead and a second lead of a plurality of leads respectively;
- a component bridging a space between the first portion of the lead frame and the second portion of the lead frame;
- an adhesive in contact with the component; and
- an integrated circuit die having a portion on the component and another portion on the adhesive.
15. The apparatus of claim 14, wherein the component is one of a dry film and a solder resist.
16. The apparatus of claim 14, wherein the integrated circuit die is electrically connected to at least one of the plurality of leads.
17. The apparatus of claim 14, further comprising a third portion of the lead frame and a fourth portion of the lead frame electrically isolated from each other.
18. The apparatus of claim 17, wherein the first portion of the lead frame and the third portion of the lead frame are electrically connected to each other, and the second portion of the lead frame and the fourth portion of the lead frame are electrically connected to each other.
19. The apparatus of claim 18, wherein the first portion of the lead frame and the third portion of the lead frame operate at a voltage higher than the second portion of the lead frame and the fourth portion of the lead frame.
20. The apparatus of claim 14, wherein a plane along a surface of the adhesive is coplanar with a plane along a surface of the component.
Type: Application
Filed: Aug 26, 2019
Publication Date: Dec 19, 2019
Inventors: Chang-Yen Ko (New Taipei City), Chung-Ming Cheng (New Taipei City), Megan Chang (New Taipei City), Chih-Chien HO (New Taipei City)
Application Number: 16/550,834