Using a laser to place known good die

Using a laser to place known good die at 100 million units/hour July massively-parallel laser die placement

Uniqarta, Inc. • Founded 2013 • Cambridge, MA and Fargo, ND • Six employees (3 Ph. D’s) • Funded by individual investors and government grants Ultra-thin chip assembly flexible display driver Ultra-fast chip assembly Laser Enabled Advanced Packaging (LEAP) 2

Emerging Electronics Require New Manufacturing Capabilities Thinner/Flexible Internet-of-Things 3 Wearable Electronics Faster/Cheaper LED Lighting Displays Structural Electronics

Today’s Placement Technology is Unusable for Tomorrow’s Products Emerging Display/Lighting Products Require Placement of Millions of LEDs If today’s placement technology is used: • Manufacture time for one unit: >1 month • Minimum LED size: 300 µm (10 -50 X larger than required 4

Laser-Enabled Massively Parallel Transfer • Ultra-fast placement (>100 million units/hour) • Known good die selectivity • Wide range of component types and sizes • Large or small display formats 5

Actuation Mechanism: Thermo-Mechanical Laser Transfer 1. Diced wafer attached to transparent carrier 2. Laser focused at selected die 3. Dynamic release layer blisters -> detaches die from carrier -> directs it to substrate 6 laser pulse dynamic release layer transparent carrier die 10 – 100 µm substrate 3 D confocal image of DRL blisters (blister side up) DRL blister (post-die release)

Laser Actuation Enables Ultra-High Placement Rates • Laser blistering mechanism: 50 µs Places dies >1000 x faster than mechanical means • Beam scanning: 8 m/s Places dies in rapid succession • Beam splitting Places multiple dies in parallel 7

Single- and Multi-Beam Modes Used for Known-Good-Die Placement 1. Bad Die Removal single-beam mode bad dies 8 3. Fill-In single-beam mode transfer field Wafer Substrate 2. Good Die Placement multi-beam mode placed dies (none) missing dies fullypopulated substrate

Modeled Placement Rates today’s placement rates: 0. 01 – 0. 05 M/hr 1080 p 4 K 9 5. 5 Inches • beam scanning • placement • wafer movement • bad die removal • wafer replacement & replacement 70 Inches

Multi-beam Arrays Most Effective at High Wafer Yields 4 K Resolution, 70 Inches 10 today’s placement time: 20 – 100 days 4 K Resolution, 5. 5 Inches

Simultaneous 5 x 5 Array Transfers Demonstrated view from above looking through glass carrier 5 x 5 array transfer video glass carrier die size: 45 x 45 µm locations of previously transferred dies 5 x 5 array to be transferred untransferred dies on carrier underside 11 Mechanical stepper being replaced by electronic scanner 4 Q 17

2017 Development Activity • Scanned arrays • Reduced die size • Mini. LED and micro. LED circuit connections • Improved accuracy 12