Patent US3795848A successfully refreshed from Google Patents.
EP0350833A2
Expired / Lapsed
EP
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Integrated circuit package structure
Assignee: Fujitsu Ltd
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Filing: 1989-07-10
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Granted: —
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Expires: 2009-07-10
Abstract
Abstract An integrated circuit, for example a hybrid integrated circuit, including a circuit substrate (2) on which active and/or passive elements (6, 7, 7′) are formed, a lead frame (9) having a support plate (8) which has an opening (80a) therein and supports the circuit substrate (2) thereon, and a mold (4) of resin for packaging the circuit substrate (2), support plate (8), and inner leads (31) of the lead frame. A bottom surface of the circuit substrate (2) is exposed and made free to contact the mold resin through the opening (8a). The integrated circuit has a ratio of exposed bottom surface to total bottom surface greater than 50%, and preferably has a ratio of surface area of the circuit substrate (2) to principal surface area of the mold (4) greater than 60%. This structure relieves mechanical stress caused in the mold package and eliminates or reduces occurrences of crack defects in the mold. Further, an integrated circuit package structure for avoiding or reducing deformation thereof is provided in accordance with the invention in which mold thicknesses above (x₁) and below (x₂) the circuit substrate (2) are selectively chosen (Fig. 15(b)). Further, an integrated circuit package structure is provided in accordance with the invention in which elements can be mounted on both main surfaces of a base member (5) (Figs. 11).
Inventors
- 👤 Toshio C/O Fujitsu Limited Matsuzaki
- 👤 Hiroaki C/O Fujitsu Limited Toshima
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 13:45
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/22; H05K3/28; H05K3/284; H10; H10W; H10W70/00; H10W70/40; H10W70/411; H10W70/421; H10W70/424; H10W70/427; H10W70/464; H10W70/468; H10W74/00; H10W74/10; H10W74/111; H10W90/00; H10W90/701; H10W90/751; H10W90/756
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
146 words
An integrated circuit, for example a hybrid integrated circuit, comprising:- a circuit substrate, comprising a base member and at least one semiconductor element, an active element or a passive element, disposed on the base member, a lead frame comprising at least a plurality of leads and a support plate, respectively provided at outward and inward portions of the lead frame, and each lead having an inner lead portion and an outer lead portion, the circuit substrate being disposed on the support plate and selectively connected with inner ends of inner lead portions, a mold of resin material packaging the circuit substrate, support plate and inner lead portions, and the support plate having an opening for exposing the bottom surface of the circuit substrate to the mold, and a ratio of the exposed bottom surface area to the entire bottom surface area thereof being greater than 50%.
Claim 2
Dependent Claim
146 words
An integrated circuit, for example a hybrid integrated circuit, comprising:- a circuit substrate, comprising a base member and at least one semiconductor element, an active element or a passive element, disposed on the base member, a lead frame comprising at least a plurality of leads and a support plate, respectively provided at outward and inward portions of the lead frame, and each lead having an inner lead portion and an outer lead portion, the circuit substrate being disposed on the support plate and selectively connected with inner ends of inner lead portions, a mold of resin material packaging the circuit substrate, support plate and inner lead portions, and the support plate having an opening for exposing the bottom surface of the circuit substrate to the mold, and a ratio of the exposed bottom surface area to the entire bottom surface area thereof being greater than 50%.
Claim 3
Dependent Claim
27 words
An integrated circuit as claimed in claim 1, wherein said ratio of the exposed bottom surface area to the entire bottom surface area is greater than 90%.
Claim 4
Dependent Claim
32 words
An integrated circuit as recited in claim 1 or 2, wherein the base member is of insulating material, for example alumina ceramic, epoxy glass, glass coated metal, oxide covered silicon, or sapphire.
Claim 5
Dependent Claim
23 words
An integrated circuit as claimed in claim 1, 2 or 3, wherein the lead frame is of copper alloy or iron nickel alloy.
Claim 6
Dependent Claim
59 words
An integrated circuit as claimed in any preceding claim, wherein the support plate comprises four stages arranged at respective corners of either a square shape or a rectangular shape, the stages being spaced apart and supporting the circuit substrate, and the bottom surface area of the circuit substrate being not larger than that of the square or rectangular shape.
Claim 7
Dependent Claim
24 words
An integrated circuit as claimed in claim 5, wherein each stage is provided with a single support bar arranged in an outward diagonal direction.
Claim 8
Dependent Claim
37 words
An integrated circuit as claimed in claim 5, wherein each stage is provided with two support bars, the directions thereof forming a right angle, each direction being parallel to a side of the square or rectangular shape.
Claim 9
Dependent Claim
54 words
An integrated circuit as claimed in claim 5, wherein each stage is provided with three support bars, the directions of two of those support bars forming a right angle, each direction being parallel to a side of the square or rectangular shape, and the remaining support bar being arranged in an outward diagonal direction.
Claim 10
Dependent Claim
54 words
An integrated circuit as claimed in claim 5, 6, 7 or 8, wherein the four stages are formed in two pairs, each of two adjacent stages, the two stages of each pair being mutually connected by a connecting bar therebetween, the connecting bar having a width less than a side dimension of a stage.
Claim 11
Dependent Claim
43 words
An integrated circuit as claimed in claim 5, 6, 7 or 8, wherein the support plate further comprises four connecting bars, each connecting bar connecting two adjacent stages with each other and having a width less than a side dimension of a stage.
Claim 12
Dependent Claim
69 words
An integrated circuit as claimed in claim 6, 7 or 8, or claim 9 or 10 when read as appended to claim 6, 7 or 8, wherein each support bar is bent, resulting in a lowering of the level of the four stages from the principal level of the lead frame, whereby a level difference between a front surface of the circuit substrate to inner lead parts is reduced.
Claim 13
Dependent Claim
35 words
An integrated circuit as claimed in claim 11, wherein inner lead parts are further bent upwardly and inside ends thereof are raised higher than the principal level, whereby the said level difference is further reduced.
Claim 14
Dependent Claim
35 words
An integrated circuit as claimed in claim 11 or 12 when read as appended to claim 9 or 10, wherein the or each connecting bar has two downwardly sloped portions and a horizontal portion therebetween.
Claim 15
Dependent Claim
32 words
An integrated circuit as claimed in claim 11 or 12 when read as appended to claim 9 or 10, or as claimed in claim 13, wherein each connecting bar has an undulation.
Claim 16
Dependent Claim
42 words
An integrated circuit as claimed in any of claims 5 to 14, wherein each stage is formed in a shape providing a pair of upper and lower clipper or pincer portions, a fringe of the circuit substrate being clipped or pinched therebetween.
Claim 17
Dependent Claim
22 words
An integrated circuit as claimed in any preceding claim, having semiconductor elements on both upper and lower surfaces of the base member.
Claim 18
Dependent Claim
23 words
An integrated circuit as claimed in any preceding claim, being a hybrid integrated circuit with at least one active and one passive element.
Claim 19
Dependent Claim
51 words
An integrated circuit as claimed in any preceding claim, wherein the mold is further formed such that the ratio of a mold thickness above the base member to that below the base member is substantially proportional to the ratio of expansion of the base member to that of the support plate.
Claim 20
Dependent Claim
40 words
An integrated circuit as claimed in claim 18, wherein a mold thickness above the base member is smaller than that below the base member when the base member is of alumina ceramic and the support plate is of copper alloy.
Claim 21
Dependent Claim
45 words
An integrated circuit as claimed in claim 18, wherein a mold thickness above the base member is larger than that below the base member when the base member is of alumina ceramic and the support plate is of a nickel-iron alloy (for example 42 alloy).
Claim 22
Dependent Claim
32 words
An integrated circuit as claimed in any preceding claim, the ratio of a surface area of the circuit substrate to a principal surface area of the mold package being greater than 60%.
Claim 23
Dependent Claim
143 words
An integrated circuit, for example a hybrid integrated circuit, comprising:- a circuit substrate, comprising a base member and at least one semiconductor element, an active element or a passive element, disposed on the base member, a lead frame comprising at least a plurality of leads and a support plate, respectively provided at outward and inward portions of the lead frame, and each lead having an inner lead portion and an outer lead portion, the circuit substrate being disposed on the support plate and selectively connected with inner ends of inner lead portions, a mold of resin material packaging the circuit substrate, support plate and inner lead portions, wherein the ratio of a mold thickness above the base member to that below the base member is substantially proportional to the ratio of the expansion of the base member to that of the support plate.
Claim 24
Dependent Claim
143 words
An integrated circuit, for example a hybrid integrated circuit, comprising:- a circuit substrate, comprising a base member and at least one semiconductor element, an active element or a passive element, disposed on the base member, a lead frame comprising at least a plurality of leads and a support plate, respectively provided at outward and inward portions of the lead frame, and each lead having an inner lead portion and an outer lead portion, the circuit substrate being disposed on the support plate and selectively connected with inner ends of inner lead portions, a mold of resin material packaging the circuit substrate, support plate and inner lead portions, wherein the ratio of a mold thickness above the base member to that below the base member is substantially proportional to the ratio of the expansion of the base member to that of the support plate.
References Cited (Backward Citations)
No citation records indexed.
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