Die attach solder paste is a high-performance electronic packaging material specifically designed for the soldering of chips to substrates (such as ceramic, metal, or PCB). It achieves high thermal conductivity and high reliability die attach connections through metallurgical bonding, replacing traditional adhesives (such as silver paste).

I. Core Functions and Positioning

• Application Scenarios:
  • Mainly used in semiconductor packaging (e.g., IGBT, SiC modules), LED chips (flip-chip/wire-bond), Mini/Micro LED displays, automotive electronics, and other high-power, high-density device packaging.
  • Replaces silver paste: Solves problems of traditional silver paste such as poor thermal conductivity (only 1.5-25 W/m·K), easy aging, and high cost.
• Core Advantages:
  • Ultra-high Thermal Conductivity: Tin-based alloys (e.g., SnAgCu, SnSb10) have thermal conductivity up to 45-67 W/m·K, 3-5 times that of silver paste, significantly reducing chip junction temperature (measured decrease up to 16%).
  • High Reliability: Solder joint shear strength >40MPa (2-3 times that of silver paste), passing stringent tests (e.g., AEC-Q200 vibration, -40℃~125℃ thermal shock).
  • Precision Soldering: Ultra-fine powder (T6/T7 grade, 5-15μm), can fill micron-level gaps (void rate <5%), adaptable to Mini LED and other micro-chips (as small as 0.127mm).

II. Technical Characteristics

• Material Composition:
  • Alloy Composition: Commonly used SnAgCu(SAC305), SnSb10, SnBiAg, etc., with melting points covering 138℃ (medium temperature) to 300℃ (ultra-high temperature), adapting to different temperature resistance requirements.
  • Flux: Low-residue, highly thixotropic formula, ensuring dispensing accuracy (viscosity 10,000-25,000cps). Residues after soldering are minimal and do not affect optical performance.
• Process Adaptability:
  • Packaging Methods: Supports dispensing by dispensing machines/die bonders (syringe packaging) or stencil printing, with dispensing cycles as fast as 240ms.
  • Curing Methods: Reflow soldering (recommended) or constant temperature soldering station, completing soldering within 5 minutes (silver paste requires 30 minutes).

III. Typical Application Areas

IV. Key Parameters and Selection Guide

• Selection Criteria:
  • Temperature Resistance Requirements: For high-temperature scenarios (>200℃), choose SnSb10 (melting point 280℃); for heat-sensitive chips, choose medium-temperature SnBiAg (melting point 138-183℃).
  • Precision Requirements: For small-sized chips (<20mil), prioritize T7 powder (2-12μm).
• Storage and Use:
  • Requires refrigeration at 2-10℃; warm to room temperature for 1 hour before use.
  • It is recommended to use within 48 hours after opening.