EP0546285A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Electronic package assembly with protective encapsulant material
Assignee: International Business Machines Corp
•
Filing: 1992-10-19
•
Granted: —
•
Expires: 2012-10-19
Abstract
Abstract An electronic package assembly (10) wherein a low profile package is soldered to an organic (e.g., epoxy resin) substrate (11) (e.g., printed circuit board), the projecting conductive leads (21) of the package and the solder (53) which substantially covers these leads (and respective conductors on the substrate) having been substantially covered with encapsulant material (61) (e.g., polymer resin) to provide reinforcement for the solder-lead connections. The encapsulant material is dispensed about the solder and lead joints following solder reflow and solidification so as to substantially surround the solder and any portions of the leads not covered with solder. The invention has particular useful with thin, small outline package (TSOP) structures which occupy a minimum of height on the substrate surface.
Inventors
- 👤 Barry Alan Bonitz
- 👤 James Vernon Ellerson
- 👤 Kishen Narain Kapur
- 👤 Jack Marlyn Mccreary
- 👤 Irving Memis
- 👤 Gerald Michael Vettel
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 20:13
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/22; H05K3/28; H05K3/284; H05K3/30; H05K3/32; H05K3/34; H05K3/341; H05K3/3421; H05K2201/00; H05K2201/10; H05K2201/10613; H05K2201/10621; H05K2201/10689; H05K2201/10954; H05K2201/10977; H10; H10W; H10W72/00; H10W72/50; H10W72/531; H10W72/5363; H10W90/00; H10W90/701; H10W90/751; H10W90/756; Y; Y02; Y02P; Y02P70/00; Y02P70/50; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T29/49144; Y10T29/49146
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
168 words
An electronic package assembly (10) comprising: an organic substrate (11) including a surface (19) thereon having a plurality of electrical conductors (17) positioned on said surface; an electronic package including an elongated, electrically insulative housing located (31) on or above said surface of said organic substrate and including first (33, 34) and second (35, 36) opposing sides, said package further including first and second pluralities of electrically conductive leads (21) projecting from said first and second opposing sides, respectively, and electrically connected to respective ones of said electrical conductors on said surface of said substrate; a plurality of quantities of solder (53), each quantity of solder substantially covering one of said conductive leads and at least a portion of a respective one of said electrical conductors to provide an electrical connection therebetween; and encapsulant material (61) located on said quantities of solder and substantially covering said solder, said encapsulant material substantially preventing electrical disconnection between said conductive leads and said solder during operation of said electronic package assembly.
Claim 2
Dependent Claim
168 words
An electronic package assembly (10) comprising: an organic substrate (11) including a surface (19) thereon having a plurality of electrical conductors (17) positioned on said surface; an electronic package including an elongated, electrically insulative housing located (31) on or above said surface of said organic substrate and including first (33, 34) and second (35, 36) opposing sides, said package further including first and second pluralities of electrically conductive leads (21) projecting from said first and second opposing sides, respectively, and electrically connected to respective ones of said electrical conductors on said surface of said substrate; a plurality of quantities of solder (53), each quantity of solder substantially covering one of said conductive leads and at least a portion of a respective one of said electrical conductors to provide an electrical connection therebetween; and encapsulant material (61) located on said quantities of solder and substantially covering said solder, said encapsulant material substantially preventing electrical disconnection between said conductive leads and said solder during operation of said electronic package assembly.
Claim 3
Dependent Claim
17 words
The electronic package assembly according to claim 1 wherein said organic substrate comprises epoxy resin dielectric material.
Claim 4
Dependent Claim
19 words
The electronic package assembly according to claim 2 wherein said substrate includes at least one conductive layer located therein.
Claim 5
Dependent Claim
24 words
The electronic package assembly according to any one of the preceding claims wherein said organic substrate is relatively thick in comparison to the housing.
Claim 6
Dependent Claim
46 words
The electronic package assembly according to any one of the preceding claims wherein said electrically insulative housing includes at least one semiconductor device (41) therein, said semiconductor device being electrically coupled to selected ones of said electrically conductive leads projecting from said sides of said housing.
Claim 7
Dependent Claim
43 words
The electronic package assembly according to claim 5 wherein the coefficients of thermal expansion of said housing having said semiconductor device therein and said conductive leads of said electronic package are substantially different than the coefficient of thermal expansion of said organic substrate.
Claim 8
Dependent Claim
38 words
The electronic package assembly according to claim 6 wherein said electrically insulative housing is comprised of a plastic material, said conductive leads are comprised of copper and said organic substrate is comprised of an epoxy resin dielectric material.
Claim 9
Dependent Claim
19 words
The electronic package assembly according to any one of the preceding claims wherein said solder is 63:37 tin:lead solder.
Claim 10
Dependent Claim
23 words
The electronic package assembly according to any one of the preceding claims wherein said encapsulant material is a polymer resin, preferably an epoxy.
Claim 11
Dependent Claim
38 words
The electronic package assembly according to any one of the preceding claims wherein said encapsulant material is also located under at least a portion of said housing of said electronic package between said housing and said organic substrate.
Claim 12
Dependent Claim
28 words
The electronic package assembly according to any one of the preceding claims wherein said encapsulant material is located substantially about the entire outer periphery of said insulative housing.
Claim 13
Independent Claim
139 words
A method of making an electronic package assembly, said method comprising: providing an organic substrate including a surface thereon having a plurality of electrical conductors positioned on said surface; positioning an electronic package having an elongated, electrically insulative housing including first and second opposing sides and first and second pluralities of electrically conductive leads projecting from said first and second opposing sides, respectively, such that said housing is located on or above said surface of said substrate and said conductive leads are electrically connected to respective ones of said electrical conductors on said surface of said substrate; substantially covering each of said conductive leads and at least a portion of a respective electrical conductor with a quantity of solder, said solder providing an electrical connection between said lead and respective conductor; and substantially covering said solder with encapsulant material.
Claim 14
Independent Claim
139 words
A method of making an electronic package assembly, said method comprising: providing an organic substrate including a surface thereon having a plurality of electrical conductors positioned on said surface; positioning an electronic package having an elongated, electrically insulative housing including first and second opposing sides and first and second pluralities of electrically conductive leads projecting from said first and second opposing sides, respectively, such that said housing is located on or above said surface of said substrate and said conductive leads are electrically connected to respective ones of said electrical conductors on said surface of said substrate; substantially covering each of said conductive leads and at least a portion of a respective electrical conductor with a quantity of solder, said solder providing an electrical connection between said lead and respective conductor; and substantially covering said solder with encapsulant material.
Claim 15
Dependent Claim
15 words
The method according to claim 12 wherein said solder is applied using a screening operation.
Claim 16
Dependent Claim
43 words
The method according to claim 13 wherein said solder is applied in paste form and thereafter heated such that said solder will reflow to thereby substantially cover respective pairs of one of said conductive leads and a respective one of said electrical conductors.
Claim 17
Dependent Claim
28 words
The method according to claim 12 wherein said organic substrate is heated to a predetermined temperature prior to said substantially covering of said solder with said encapsulant material.
Claim 18
Dependent Claim
26 words
The method according to claim 15 wherein said heating is accomplished by placing said organic substrate in a hot air oven for a pre-established time period.
Claim 19
Independent Claim
53 words
The method according to any one of the preceding claims 12 to 16 wherein said encapsulant material is applied in substantially liquid form and thereafter heated to a pre-established temperature for a predetermined time period sufficient to cure said encapsulant material, preferably said time period is from about three to about four hours.
Claim 20
Dependent Claim
27 words
The method according to claim 17 wherein said encapsulant material is heated to approximately the glass transition temperature of said organic substrate for said predetermined time period.
Claim 21
Dependent Claim
25 words
The method according to claim 18 wherein said pre-established temperature is within the range of from about 110 degrees Celsius to about 140 degrees Celsius.
References Cited (Backward Citations)
US4238528A
Cited
US4830922A
Cited
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.