I. Laser Solder Paste
Laser solder paste is a specialized solder paste designed for laser soldering processes. It uses a laser as the heat source, leveraging its high energy density to achieve rapid, localized heating, causing the solder paste to melt and complete the solder joint. Its core advantage lies in solving the challenges of soldering in micro-areas and on temperature-sensitive components, making it a key material for the miniaturization and precision development in electronic manufacturing.
Core Features
- Non-contact Soldering: The laser does not need to contact the components, avoiding mechanical stress and electrostatic damage caused by traditional soldering (e.g., soldering iron).
-
High Precision: The smallest laser spot can be as fine as
0.1mm, suitable for soldering micro-pitch (<0.3mm) and tiny solder joints. - Low Thermal Impact: Only heats the local solder joint, causing no thermal damage to surrounding components (e.g., plastic antenna bases, flexible circuit boards).
-
Fast and Efficient: Soldering time can be as short as
300 milliseconds, much faster than traditional reflow soldering. -
Environmentally Friendly and Reliable: Halogen-free formula (
ROL0grade), low residue, no-clean. By adding anti-spatter agent, achieves no solder splash and no solder balls. - Strong Adaptability: Heating parameters can be adjusted according to component type, supporting various processes such as dispensing, printing, and pin transfer.
Composition and Specifications
| Category | Details |
|---|---|
| Alloy Composition |
Divided into high, medium, and low-temperature series: - High temperature: Sn96.5Ag3Cu0.5 (Melting point 217℃)- Medium temperature: Sn64Bi35Ag1 (Melting point 172℃)- Low temperature: Sn42Bi58 (Melting point 138℃)
|
| Solder Powder Particle Size | Classified according to IPC standards from 3# (25-45μm) to 7# (<5μm). Among them, 6#, 7# powders are suitable for ultra-precision applications. |
| Flux Characteristics |
Adds photosensitive material (rapidly absorbs laser energy); viscosity 100±20Pa·s; high insulation.
|
Typical Applications
- Electronic Manufacturing: IC packaging, semiconductor bumps (BGA), micro-sensors.
- Automotive Electronics: Engine sensors, braking system sensors, and other high-reliability scenarios.
- Consumer Electronics: Camera modules (CCM), VCM voice coil motors, FPC flexible boards, connector terminals.
- Optical Communication: Optical fiber connectors, optical modules, etc.
II. Hot-bar Solder Paste
Hot-bar solder paste is a specialized solder paste designed for Hot-bar soldering (hot-pressure head heating) processes. It achieves soldering by transferring heat through contact with a hot-pressure head, rapidly heating the solder paste to its melting point. Its core advantages are speed and no residue, making it particularly suitable for precision soldering in mass production scenarios.
Core Features
-
Ultra-fast Soldering: Soldering time can be as short as
300 milliseconds, much faster than traditional soldering iron. - No Residue Contamination: No solvent volatilization during soldering, no solder ball residue, no-clean, eliminating subsequent processes.
-
Environmentally Friendly and Safe: Halogen-free formula, transparent residue, high surface impedance (
>1×10⁸Ω). -
Process Adaptability: Suitable for dispensing, printing, pin transfer processes, can use needles with inner diameter
0.15~0.25mmwithout clogging. -
Good Stability: Small change in viscosity during continuous printing, long steel stencil operable time (
>8 hours).
Composition and Specifications
| Category | Details |
|---|---|
| Alloy Composition |
Common Sn96.5Ag3Cu0.5 (217℃), Sn64Bi35Ag1 (172℃), Sn42Bi58 (138℃).
|
| Solder Powder Particle Size | Commonly 3# (25-45μm) to 6# (10-20μm), among which 4#, 5# powders are suitable for wireless charging, data cables and other applications. |
| Flux Characteristics |
Special active system, viscosity 100±20Pa·s, smooth dispensing, high insulation. Requires sealed storage at 0-10℃.
|
Typical Applications
- Consumer Electronics: Wireless charging (coil to PCB soldering), Type-C interfaces, data cables, camera modules.
- Optical Communication: Optical module terminals, heat-sensitive/photosensitive components.
- Precision Instruments: Hard drive magnetic heads, speakers/loudspeakers, miniature circuits for medical devices.
III. Core Differences Between the Two
| Dimension | Laser Solder Paste | Hot-bar Solder Paste |
|---|---|---|
| Heating Method | Laser non-contact heating (thermal radiation) | Hot-pressure head contact heating (thermal conduction) |
| Precision Requirement | Higher (suitable for micron-level solder joints) | Higher (suitable for millimeter-level solder joints) |
| Heat Affected Zone | Extremely small (<0.5mm) | Smaller (<1mm) |
| Applicable Scenarios | Ultra-precision, temperature-sensitive components (e.g., semiconductor packaging) | Mass production, fast production (e.g., wireless charging, data cables) |
| Type | Melting Point Range (℃) | Core Alloy Example | Applicable Scenarios and Products |
|---|---|---|---|
| Laser high-silver solder paste | ~217 |
Sn96.5/Ag3.0/Cu0.5
|
Electronic manufacturing, automotive electronics, consumer electronics, optical communication Products: EL-S3/S4/S5/S6
|
| Hot-bar high-silver solder paste | ~217 |
Sn96.5/Ag3.0/Cu0.5
|
Electronic manufacturing, automotive electronics, consumer electronics, optical communication Products: EH-S3/S4/S5/S6
|
Summary
Both laser solder paste and hot-bar solder paste are precision soldering materials in electronic manufacturing. The former focuses on "ultra-precision, low-damage", making it an ideal choice for miniaturized soldering; the latter focuses on "high efficiency, mass production", showing clear advantages in automated production lines. As electronic devices evolve towards miniaturization and high reliability, the application of both in automotive electronics, consumer electronics, optical communication and other fields will continue to expand, becoming core supporting materials for future soldering technology.
