Overview

Amkor has applied its WLFO technology know-how,

taking Wafer Level CSP (WLCSP) to the next packaging

generation: WLCSP+.

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Recon wafer is created with KGD (Known Good Die)

placed with very small distance between dies

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All solder balls are placed in the fan-in zone

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Mold compound offers 5-side mechanical die

protection (sidewalls and optional backside

protection)

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Compared to WLCSP, WLCSP+ offers an additional

50% increase in die strength

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Diced die test on wafer-level without bare die

handling

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Components can be delivered in JEDEC tray without

risk

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WLCSP manufacturing in highly efficient 300 mm

WLFO recon wafer, independent of wafer diameter

provided by the customer

Design Features

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Supports 300 mm wafer diameter

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Single/multi-layer Cu RDL, with and without Cu UBM

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Max package size: 23 x 25 mm2 (largest in the

market)

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Min package thickness: 0.4 mm (thinner under

validation)

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Plated RDL line/space width: 20/20 μm (10/10 μm

under validation)

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Bump height and pitch: 0.25 mm @ 0.5 mm (down

to 0.2 mm @ 0.4 mm under validation)

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Backside coating optional

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Standard laser marking and packing in tape and reel

Applications

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Mobile and consumer products, handsets

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Wireless connectivity including Bluetooth, WLAN,

RF, FM radio, GPS

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PMIC, PMU, high performance computing

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Analog and other ICs such as MEMS and Sensors

WLCSP+

Performance

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Electrical: Low parasitics due to short connections

(WLCSP), thick Cu- RDL and choice of dielectric

material (LTC-PI). Dependent on design and

application suitable for 10 GHz and beyond

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Thermal: Depending on die size and whether

backside die is molded/exposed (e.g., 5 x 5 mm2 die,

molded backside die: Rth = 30 K/W)

Performance Data: Reliability

6.6 x 7.1 x 0.4 mm3, 98 bumps, 500 µm pitch; WLCSP+

with 30 µm sidewall + backside mold. Stack-up: PBO/Cu

RDL/PBO/Cu UBM.

Component Level Tests

Test

Specification

Criteria

Moisture Sensitivity

Level (MSL)

IPC/JEDEC J-STD-020

MSL1 For Lead-free,

168 Hrs at 85°C/85%

RH

Temperature Cycling

(TC)

JESD22-A104,

Condition B

-55°C/125°C,

2 Cy/Hour, 1000 Cycles

High Temperature

Storage (HTS)

JESD22-A103,

Condition B

150°C, 2000 Hours

Unbiased HAST

(uHAST)

JESD22-A118,

Condition A

130°C/85% RH,

96 Hours

Board Level Tests

Test

Specification

Criteria

Drop Test

JESD22-B111

30 Drops

Temperature Cycling

on Board (TCoB)

IPC-97-01

-40°C/125°C,

1 Cy/Hour, 1000x