EPOXY MOLDING COMPOUNDS
Paint chemicals 2025-03-21
EME (epoxy molding compounds) possess excellent moldability, good mechanical and electrical properties, and high reliability. It is mainly used for semiconductor component packaging, especially for IC (integrated circuits), diodes, transistors, photocouplers, and coils.
Epoxy Molding Compounds: Properties and Applications
Table 1: Key Characteristics of Epoxy Molding Compounds
| Property | Typical Value | Functional Benefit |
|---|---|---|
| Base Resin | Epoxy novolac/biphenyl | High thermal/chemical resistance |
| Filler Content | 70-90% silica | Low CTE, high strength |
| Glass Transition Temp | 120-160°C | Heat resistance |
| Flexural Strength | 120-180 MPa | Structural integrity |
| CTE (ppm/°C) | 8-15 (below Tg) | Dimensional stability |
Table 2: Comparison with Other Encapsulation Materials
| Parameter | Epoxy Molding | Silicone | Polyimide |
|---|---|---|---|
| Max Temp | 175°C | 200°C | 300°C |
| Moisture Absorp. | 0.1-0.3% | 0.4-0.6% | 0.8-1.2% |
| Cure Time | 1-3 min | 10-30 min | 30-60 min |
| Cost Factor | 1.0 | 3.0 | 5.0 |
| Processability | Excellent | Good | Fair |
Table 3: Common Applications
| Application | Key Requirements | Compound Type |
|---|---|---|
| IC Packaging | Low α-particle emission | High purity grade |
| Power Devices | High thermal conductivity | Filled with AlN |
| LED Packaging | High reflectivity | White pigment added |
| Automotive | Thermal cycling resistance | Flexible formulation |
| Consumer Electronics | UL94 V-0 rating | Flame retardant |
Table 4: Processing Parameters
| Parameter | Range | Effect on Quality |
|---|---|---|
| Mold Temp | 165-185°C | Affects flow and cure |
| Injection Pressure | 5-15 MPa | Determines filling |
| Cure Time | 60-180 sec | Complete crosslinking |
| Post Cure | 4h@175°C | Final properties |
Table 5: Reliability Test Results
| Test Method | Condition | Performance |
|---|---|---|
| MSL | L1. 260°C reflow | Pass 3 cycles |
| THB | 85°C/85%RH, 1000h | <5% failure |
| TCT | -55°C to 150°C, 500 cycles | No delamination |
| HAST | 130°C/85%RH, 96h | <1% weight gain |
Epoxy molding compounds offer optimal balance of processability, reliability and cost for semiconductor encapsulation. Their formulation flexibility allows customization for specific thermal, mechanical and electrical requirements in various electronic applications.
