Name: Bonding PCB
Brand: PCB Printed Circuit Board and PCBA manufacturing
Rating: 5 (1 reviews)

Description
Data Sheet

What is Bonding PCB?

Bonding PCB is a specialized circuit board tailored for chip wire bonding processes in semiconductor packaging. Before encapsulation, it adopts gold wire or aluminum wire bonding to electrically connect chip internal circuits with packaging pins or gold-plated copper foil pads on the PCB.

Relying on ultrasonic bonding technology, an ultrasonic generator outputs 40~140 kHz high-frequency vibration. Vibration energy is transmitted to the bonding capillary via a transducer and amplitude transformer. Under precise pressure and high-frequency friction, the oxide layer on metal surfaces is destroyed to produce micro plastic deformation. Two pure metal surfaces form atomic-level close contact, creating high-strength mechanical and electrical integration. After wire bonding is completed, the chip and connecting wires are fully sealed and protected with black epoxy adhesive to finish packaging.

How to Identify Bonding PCB

Bonding PCB has distinct structural features for quick identification:

Bonding pads are arranged in a regular rectangular array, with compact square or circular pad design and ultra-fine pitch;
Solder mask adopts targeted open-window design, with independent regular open-window pads reserved in the central IC bonding area, and leading-out traces for most bonding terminals;
Dimensional acceptance standards: bonding foot width tolerance ±10%, pad spacing ≥ 3mil;
No broken bonding pins are allowed, and etching edges cannot be narrowed to reduce the designed spacing.

Advantages of Bonding PCB Packaging

Compared with traditional SMT mounting technology, bonding packaging delivers comprehensive performance upgrades:

Higher resistance to corrosion, shock and long-term operational stability;
Chips are connected to PCB pads through fine gold wires and fully covered by high-performance organic protective adhesive;
Sealed isolation effectively prevents damage from humidity, static electricity and chemical corrosion;
The protective colloid melts and cures at a specific high temperature to form a seamless fit with the chip, eliminating mechanical wear of core components and greatly improving product service life and environmental adaptability.

PCB Bonding Standard Process Requirements

Complete Process Flow

PCB Cleaning → Dispensing → Die Attach → Wire Bonding → Glue Encapsulation → Finished Product Testing

1. PCB Surface Cleaning

Wipe off oil stains, dust and oxide layers on bonding areas. Auxiliary cleaning with soft brushes or air guns is required to ensure pad surface cleanliness and improve bonding firmness.

2. Dispensing

Control glue volume moderately, with four glue points evenly distributed at four corners of the chip area. Strictly avoid adhesive overflow and contamination of bonding pads to prevent bonding failure.

3. Die Attach

Use a flat-nozzle vacuum suction pen to pick and place chips to avoid wafer surface scratches. Verify chip orientation strictly during lamination to ensure three core requirements:

Flat: The wafer is parallel and closely fitted with the PCB without gaps;
Stable: The chip is firmly attached and not easy to fall off during subsequent processing;
Accurate: Align with the reserved position without deflection or reverse installation.

4. Wire Bonding

Unified industrial inspection standards for wire bonding quality:

Pull strength: 1.0mm wire ≥ 3.5G; 1.25mm wire ≥ 4.5G;
Aluminum wire tail specification: 0.3~1.5 times of wire diameter;
Solder joint shape: standard oval structure;
Solder joint length: 1.5~5.0 times of wire diameter;
Solder joint width: 1.2~3.0 times of wire diameter.

Operators conduct full-process microscopic monitoring to eliminate defects such as wire breakage, offset, cold solder joint, thermal welding and aluminum layer peeling. First-piece inspection is mandatory before mass production; regular sampling inspection is required every 2 hours during continuous production.

5. Glue Encapsulation

Check the flatness and integrity of the plastic ring in advance to ensure no deformation. The bottom of the plastic ring must fit closely with the wafer without blocking the photosensitive area.

The black sealing glue shall fully cover bonding aluminum wires and chips without exposure or overflowing the PCB boundary. Prohibit the glue from penetrating into the chip through the plastic ring, and avoid scratching wafers and bonding wires during dispensing.

Strict segmented curing parameters:

Preheating: 120 ± 5°C, 1.5~3.0 minutes;
Curing: 140 ± 5°C, 40~60 minutes.

After curing, the glue surface is free of pores and cracks, and the glue height shall not exceed the plastic ring.

6. Bonding PCB Comprehensive Testing

Multiple testing methods are combined to fully verify overall quality:

Manual visual inspection for appearance and structural defects;
Automatic bonding machine detection for wire connection quality;
AOI automatic optical analysis;
X-ray internal scanning to detect hidden defects of underlying solder joints.

Model: Bonding Circuit Board

Material: FR-4 Tg=130

Layer: 2 layer PCB

Color: Green/White

Finished Thickness: 1.0mm

Copper Thickness: 0.5OZ

Surface Treatment: Immersion Gold

Min Trace: 4mil(1.0mm)

Min Space: 4mil(1.0mm)

Characteristic: Bonding Circuit

Application: IC Bonding

Bonding PCB

Description

Data Sheet