Surface mount chip package having an array of solder ball contacts arranged in a circle and conductive pin contacts arranged outside the circular array

• US 5,490,040 A
• Filed: 12/22/1993
• Issued: 02/06/1996
• Est. Priority Date: 12/22/1993
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Tuozzolo, Vito J., Milliken, John C., Mosley, Joseph M., Gaudenzi, Gene J.
• Primary Examiner(s): SPARKS, DONALD ALAN
• Application Number:
  US08/172,467
• Time in Patent Office: 776 Days
• Field of Search: 228/179.1, 228/180.1, 228/180.21, 228/180.22, 228/175.1, 257/692, 257/693, 257/697, 257/698, 257/700, 257/723, 257/724, 257/728, 257/738, 257/773, 257/786, 257/690, 257/653, 257/696, 257/737, 257/734, 257/747, 257/778, 257/779 , 257/650, 257/652, 257/656, 257/, 361/760, 361/767, 361/770, 361/772, 361/773, 361/774, 361/777, 361/807, 361/808, 361/809, 361/776, 361/783, 361/784, 361/820, 437/204, 437/209, 437/183, 439/68, 439/69, 439/74, 439/75, 439/76, 439/78, 439/83, 439/84, 439/72, 439/65, 439/72, 174/52.1, 174/260
• US Class Current: 361/773
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/73253 Bump and layer connectors
• CPC Class Codes: H01L 23/49811 Additional leads joined to the metallisation on the insulating substrate, e.g. pins, bumps, wires, flat leads H01L23/49827 takes precedence
• CPC Class Codes: H01L 23/49816 Spherical bumps on the substrate for external connection, e.g. ball grid arrays [BGA]
• CPC Class Codes: H01L 23/49838 Geometry or layout
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01322 Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/15311 being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/16152 Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H05K 2201/10659 Different types of terminals for the same component, e.g. solder balls combined with leads
• CPC Class Codes: H05K 2201/10734 Ball grid array [BGA]; Bump grid array
• CPC Class Codes: H05K 3/3415 on both sides of the substrate or combined with lead-in-hole components
• CPC Class Codes: H05K 3/3447 Lead-in-hole components H05K3/3415 takes precedence
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

An electrical device for logic circuits having a package comprising a combination of controlled collapse electrical interconnections, such as solder balls and pin through-hole conductors, wherein the conductors are disposed outside the perimeter of an inter-array of solder balls, which when a maximum number of solder balls are disposed, the array is circular in shape, so as to provide an increased footprint for the electrical device beyond that, otherwise maximum footprint for solder balls alone, which footprint is otherwise limited in size due to failures which occur in solder balls when solder balls are exposed to thermal and mechanical stress levels at extended distances from the neutral or zero stress point of the array.

Claims

1. A packaged electronic hardware unit having a footprint including an array of electrical connections for engagement with a circuit board for performing logic functions without incurring mechanical stress which can result in electrical discontinuity at the electrical connections, comprising:

a substrate having a center and a planar underside surface;

an electrical logic circuit have input/output terminals carried by the substrate;

individual contacts of controlled collapse electrically conductive solder material connected to some of the input/output terminals formed in the shape of balls extending downwardly from the substrate and extending in an orthogonal direction from the planar underside surface of the substrate; and

individual pins of electrically conductive material connected to other of the input/output terminals not connected to the contacts, extending downwardly from the substrate and orthogonally from the substantially planar underside surface of the substrate and disposed more outwardly from the center of the substrate than any contact to form an array of electrical connections including contacts and pins, which contacts include a maximum number of contacts forming a circular array of contacts, and which pins are disposed farther from the center of the substrate than the contacts to provide electrical connections which do not incur mechanical stress which can result in electrical discontinuity at the electrical connections.