MEMS热电堆芯片固晶工艺参数优化研究
Optimization of Die-Attach Parameters for MEMS Thermopile Chips
工艺要求量化指标
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参数
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临界范围
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失效风险
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爬胶高度（H₁）
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芯片高度15%±5%
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过低：黏结失效；过高：短路
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固晶厚度（h）
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40-60μm
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过薄：热膨胀破裂；过厚：热阻增大
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银浆宽度（d）
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240-300μm
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偏离芯片侧壁宽度±15%
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参数优化实验设计
1. 压力参数（P）
2. 点胶高度（Zdisp）与贴片高度（Zpick）
热应力仿真验证（ANSYS）
模型条件：
结果对比：
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固晶厚度(h)
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爬胶高度(H₁)
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*大热应力(MPa)
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40μm
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170μm
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152
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50μm
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150μm
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187
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60μm
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130μm
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210
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结论：h=40μm+H₁=170μm时热应力*小（降低18%↑）
实验验证（剪切强度测试）
Professional English Translation
Optimization of Die-Attach Parameters for MEMS Thermopile Chips
Core Challenges
Quantified Process Targets
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Parameter
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Critical Range
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Failure Risk
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Fillet Height (H₁)
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15%±5% of chip height
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Low: Bond failure; High: Short
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Bondline Thickness (h)
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40-60μm
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Thin: Thermal crack; Thick: High thermal resistance
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Silver Paste Width (d)
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240-300μm
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Deviation >±15% from chip width
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Parameter Optimization
1. Pressure (P)
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Range: 0.2-0.4MPa
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Findings:
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P=0.2MPa → Paste width≈240μm (Insufficient)
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P=0.3MPa → Paste width≈280μm (Optimal)
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P=0.4MPa → Paste width>300μm → h>100μm (Excessive thermal resistance)
2. Dispensing Height (Zdisp) & Pick Height (Zpick)
Thermal Stress Simulation (ANSYS)
Model Setup:
Result Comparison:
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Bondline (h)
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Fillet (H₁)
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Max Thermal Stress (MPa)
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40μm
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170μm
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152
|
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50μm
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150μm
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187
|
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60μm
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130μm
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210
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Conclusion: Min stress at h=40μm + H₁=170μm (18%↓ reduction)
Validation (Shear Strength Test)
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Equipment: Nordson DAGE 4000 Bond Tester
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Condition: Post-curing at room temperature
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Results:
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Optimized Params (P=0.3MPa, Zdisp=140μm, Zpick=460μm) → Avg. force 43.14N
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Conventional params → Avg. force <30N
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Failure Mode: Cohesive fracture in paste (non-interface) → Reliability confirmed
