EP0059926A1
Expired / Lapsed
EP
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A method for manufacturing a plastic encapsulated semiconductor device and a lead frame therefor
Assignee: Panasonic Holdings Corp
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Filing: 1982-03-02
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Granted: —
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Expires: 2002-03-02
Abstract
Abstract Disclosed is a method for manufacturing a plastic encapsulated semiconductor device and a lead frame therefor. A semiconductor device assembly is formed, using a lead frame an external lead (6) of which extends to one side of a substrate support (2) serving as a heat sink and supporting a semiconductor substrate, (1) and strips (15, 16) of which extend to the other end of the substrate support. The external lead and strips are clamped by upper and lower molds (13, 14) for plastic encapsulation. A connecting portion between the external lead (6) and a connecting band (9) and the strips (15, 16) extending from a plastic encapsulating housing to the outside are cut. The substrate support (2) is, thus, held properly at the time of plastic encapsulation, preventing bending of the semiconductor device due to injection pressure of the plastic (30). Therefore, a thin film of plastic is uniformly and with high precision formed on a lower surface of the substrate support.
Inventors
- 👤 Hiroyuki Fujii
- 👤 Kenichi Tateno
- 👤 Mikio Nishikawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 18:44
CPC Classifications
H; H10; H10W; H10W74/00; H10W74/01; H10W74/016; H10W70/00; H10W70/40; H10W70/481; H10W72/00; H10W72/01; H10W72/0198; H10W74/10; H10W74/111; H10W74/121; H10W72/015; H10W72/01515; H10W72/071; H10W72/075; H10W72/50; H10W72/541; H10W72/5449; H10W72/551; H10W72/552; H10W90/00; H10W90/701; H10W90/751; H10W90/756; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49121
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
147 words
A method for manufacturing a plastic encapsulated semiconductor device comprising the steps of clamping at least external leads and strips of a semiconductor device assembly formed using a lead frame which has a first connecting band connected to said external leads extending from one side of a substrate support further used as a heat sink and a second connecting band connected to said strips extending from the other side of said substrate support, clamping at least said external leads and said strips by upper and lower molds so that said substrate support may float in a cavity formed by said upper and lower molds, injecting a plastic into the cavity while parts of said strips are disposed in said cavity, and cutting parts of said strips which extend outside a plastic encapsulating housing and cutting a connecting portion between said external leads and said first connecting band.
Claim 2
Independent Claim
147 words
A method for manufacturing a plastic encapsulated semiconductor device comprising the steps of clamping at least external leads and strips of a semiconductor device assembly formed using a lead frame which has a first connecting band connected to said external leads extending from one side of a substrate support further used as a heat sink and a second connecting band connected to said strips extending from the other side of said substrate support, clamping at least said external leads and said strips by upper and lower molds so that said substrate support may float in a cavity formed by said upper and lower molds, injecting a plastic into the cavity while parts of said strips are disposed in said cavity, and cutting parts of said strips which extend outside a plastic encapsulating housing and cutting a connecting portion between said external leads and said first connecting band.
Claim 3
Dependent Claim
29 words
A method according to claim 1, wherein a thickness of the plastic encapsulated below said strips is larger than the thickness of the plastic encapsulated below said substrate support.
Claim 4
Dependent Claim
64 words
A method according to claim 1, wherein said cavity formed by said upper and lower molds consists of a first portion and a second portion, a distance between a top and a bottom of said first portion being larger than the distance of the second portion so as to position a semiconductor element mounting portion of said semiconductor device assembly with said first portion.
Claim 5
Dependent Claim
33 words
A method according to claim 3, wherein a mold projection for forming a through hole for mounting said semiconductor device to said substrate support with a screw is formed in said second portion.
Claim 6
Dependent Claim
22 words
A method according to claim 1, wherein a thickness of the plastic encapsulated under said substrate support is 0.3 to 0.5 mm.
Claim 7
Dependent Claim
121 words
A lead frame comprising a first connecting band, a plurality of external leads extending in one direction from said first connecting band, a substrate support which further serves as a heat sink connected to a top of one of said external leads, strips one ends of which are connected to one side of said substrate support opposite to the other side connected to said external leads, and a second connecting band extending parallel to said first connecting band with said substrate support disposed therebetween, wherein said strips have a smaller thickness than said substrate support so that a step is formed therebetween and lower surfaces of said strips are at a higher level than a lower surface of said substrate support.
Claim 8
Dependent Claim
121 words
A lead frame comprising a first connecting band, a plurality of external leads extending in one direction from said first connecting band, a substrate support which further serves as a heat sink connected to a top of one of said external leads, strips one ends of which are connected to one side of said substrate support opposite to the other side connected to said external leads, and a second connecting band extending parallel to said first connecting band with said substrate support disposed therebetween, wherein said strips have a smaller thickness than said substrate support so that a step is formed therebetween and lower surfaces of said strips are at a higher level than a lower surface of said substrate support.
Claim 9
Dependent Claim
24 words
A lead frame according to claim 6, wherein the number of strips the ends of which are connected to said substrate support is two.
Claim 10
Dependent Claim
27 words
A lead frame according to claim 6, wherein a plurality of apertures are formed in each of said first and second connecting bands at an equal pitch.
References Cited (Backward Citations)
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