Lead Frame

1. Examples
2. Successful projects

Examples

Particle Interconnect Package (PIP)

Advanced low-cost minimal IC package.

QFP 132 lead, 0.012" pitch OLB (Outer Lead Bond).	Leadframe / Chip-On-Board socket & carrier.

0.001"-0.005" flex/rigid board with flip chip attached topside (heat up/electrical down) {3 μ line & space on 3 μ flex obtainable at special labs} Board acts as probe card/burn-in socket/final package, only bad die are thrown away at assembly. Leads completely supported yet flexible and damage resistant. Outer Lead Bond (OLB) attachment by conventional heated solder reflow method or non-heated Particle Interconnect methods. Automatic or manual placement even with finest pitches. Controlled impedance routing from OLB to die pad in either single or multi-layer PCB. Lower cost than etched/stamped leadframes or conventional flip chip techniques.

Particle Interconnect lead frame package

Solder bumped chip (ILB) on Particle Interconnect lead frame (OLB).	Particle Interconnect bumped chip (ILB) on Particle Interconnect lead frame (OLB).

Alternative PI lead frame package has socket built-in at OLB

Temporary, or permanent contact even in presence of adhesive, grease, or solder.

Alternative Particle Interconnect lead frame with holddown

Removable single unit - proof of concept.

0.025" pitch, 196 lead, ceramic QFP.	0.020" pitch, 256 lead, ceramic QFP.

Alternative Particle Interconnect lead frames vs. standard packages

Successful projects

Particle Interconnect - Hughes Aircraft 1988 - 1989

50,000 die joint production test venture.

Before burned-in:

• No bump deformation.
• Die Sn/Pb 3/97, socket Au 100, load 1 gm/mil² pad to socket. Burned-in 125 ° C for 168 hours. Particles milled into gold ceramic ink and fired onto ceramic substrate. (Depression in center of bump is aluminum die pad covered by protective passivation layer.)

50x bumped chip before pressing against PI gold thick film.	500x bump before contacting PI.

After burned-in:

• No bump deformation.
• PI/gold bonded to tin/lead bump and was ripped off substrate. Resulting in using nickel as higher strength Particle Interconnect bond layer in future test socket/temporary contact usages and other metal combinations in permanent usages.

50x bumped chip after pressing against PI gold thick film metal matrix with 1 gm/mil2 load.	500x bump after contacting PI, metal matrix is on bump.

Particle Interconnect - Hughes environmental test die

Particle Interconnect removable MCM die socket.

100% of 500 die lot survived 4x Mil-Std-883C.

1. Particle Interconnect with both adhesive and mechanical hold-down of chips while accumulating 4 runs of:
• 168 hours (672 hours total) 125 ° C for burn-in (other test passed are continuous 125 ° C),
• 500 cycles (2,000 cycles total) -55 to +125 ° C fast ramp MIL-STD-883C shock test,
• 24 hours (96 hours total) in salt/fog corrosion test,
• 24 hours (96 hours total) HAST (Highly Accelerated Stress Testing) pressure chamber (30 psi, +125 ° C pressure pot),
• Results in 50,000 die lot test prior to transfer into production.
2. 96/4 Pb/Sn reflowed plated bump to spherize with special passivation configuration.
3. Die orientated same as CAD picture for clarity (see: Removable die MCM - L/D/C).
4. Note contact resistance test pads on left edge.
5. Note traces for passivation crack detection.
6. Note temperature sensors in center of die.
7. Note traces for edge crack detection.
8. Note traces for die heating.
9. Note Particle Interconnect imprint.

Particle Interconnect piercing SDRAM DDR1 package balls

• Demonstrating damage free performance when exposed to excessive loading.
• 60 pounds of force on 60 balls.
• Note minor depth of penetration.

Particle Interconnect - MMS - TI - HP bare die probe

Proof of removable Known-Good-Die. Note single layer of particle on pad.

IEEE Transactions on Components, Packaging, And Manufacturing Technology

A Bare-Chip Probe for High I/O, High Speed Testing

Alan Barber, Keunmyung Lee, and Hannsjorg Obermaier

HPL-94-18

Particle Interconnect - Sandia Lab Known Good Die (KGD)

Known-Good-Die probe/burn-in. Proof of removable die MCM-L/D/C.

• 0.030" pitch 19x19 miniBGA.
• Burn-in at 125 ° C, 168 hours.
• 0 failures, 100+ runs, no deformation.

0 failures, 11 runs shown above.	Particle Interconnect surface mount BGA socket.

Particle Interconnect - Sandia mBGA interposer schematic.	Sandia mBGA interposer