Particulate Contamination Control encompasses clean room practices, filtration systems, and procedures designed to minimize particle deposition on semiconductor wafers.

What Is Particulate Contamination Control?

• Goal: Keep particle counts below critical defect density
• Methods: HEPA/ULPA filtration, clean room protocols, equipment design
• Metrics: Particles per wafer, particles per ft³ of air
• Standard: ISO 14644 defines clean room classifications

Why Particle Control Matters

At advanced nodes, particles >20nm can cause killer defects. A single particle on a critical layer fails multiple die.

<svg viewBox="0 0 384 283" xmlns="http://www.w3.org/2000/svg" style="max-width:100%;height:auto" role="img"><rect x="0" y="0" width="384" height="283" rx="12" fill="#0d1117"/><g font-family="ui-monospace,SFMono-Regular,Menlo,Consolas,&quot;Liberation Mono&quot;,monospace" font-size="14"><text xml:space="preserve" x="20" y="31.7"><tspan fill="#c9d1d9">Particle Size vs. Node:</tspan></text><text xml:space="preserve" x="20" y="50.7"><tspan fill="#c9d1d9">Node    Critical Particle   Die Area Lost</tspan></text><text xml:space="preserve" x="20" y="69.7"><tspan fill="#6e7681">─────</tspan><tspan fill="#c9d1d9">   </tspan><tspan fill="#6e7681">─────────────────</tspan><tspan fill="#c9d1d9">   </tspan><tspan fill="#6e7681">─────────────</tspan></text><text xml:space="preserve" x="20" y="88.7"><tspan fill="#c9d1d9">180nm   &gt; 90nm              1 die</tspan></text><text xml:space="preserve" x="20" y="107.7"><tspan fill="#c9d1d9"> 45nm   &gt; 22nm              1-4 die</tspan></text><text xml:space="preserve" x="20" y="126.7"><tspan fill="#c9d1d9">  7nm   &gt; 3nm               Multiple die</tspan></text><text xml:space="preserve" x="20" y="145.7"></text><text xml:space="preserve" x="20" y="164.7"><tspan fill="#c9d1d9">Clean Room Classification (ISO 14644):</tspan></text><text xml:space="preserve" x="20" y="183.7"><tspan fill="#c9d1d9">Class   Max particles/m³ (≥0.1μm)</tspan></text><text xml:space="preserve" x="20" y="202.7"><tspan fill="#6e7681">──────</tspan><tspan fill="#c9d1d9">  </tspan><tspan fill="#6e7681">────────────────────────</tspan></text><text xml:space="preserve" x="20" y="221.7"><tspan fill="#c9d1d9">ISO 1   10</tspan></text><text xml:space="preserve" x="20" y="240.7"><tspan fill="#c9d1d9">ISO 3   1,000</tspan></text><text xml:space="preserve" x="20" y="259.7"><tspan fill="#c9d1d9">ISO 5   100,000 (typical fab)</tspan></text></g></svg>

Contamination Control Methods: