<svg viewBox="0 0 760 470" xmlns="http://www.w3.org/2000/svg" font-family="-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif"><rect x="0" y="0" width="760" height="470" rx="14" fill="#0d1117"/><text x="20" y="30" fill="#e6edf3" font-size="19" font-weight="700">Ion implantation: fire dopant atoms into the silicon to set its conductivity</text><text x="20" y="50" fill="#8b949e" font-size="12.5">Accelerate charged dopant ions into the wafer; a mask decides where, the dose &amp; energy decide how much and how deep</text><!-- Panel 1: the implanter --><rect x="20" y="66" width="226" height="298" rx="7" fill="#0c141d" stroke="#30363d"/><text x="32" y="88" fill="#7ee6c0" font-size="13" font-weight="700">1 &#183; A particle accelerator</text><text x="32" y="106" fill="#8b949e" font-size="10.5">ionize, select, accelerate, scan</text><rect x="42" y="118" width="182" height="150" rx="3" fill="#111a24" stroke="#30363d"/><!-- ion source --><rect x="50" y="150" width="24" height="20" rx="2" fill="#e0913a"/><text x="62" y="182" fill="#e0913a" font-size="7" text-anchor="middle">source</text><!-- mass analyzer (bent path) --><path d="M74,160 Q100,160 104,140" fill="none" stroke="#a99cf0" stroke-width="1.5"/><circle cx="112" cy="134" r="10" fill="none" stroke="#6b5fb0" stroke-width="1.2"/><text x="112" y="120" fill="#a99cf0" font-size="6.5" text-anchor="middle">mass select</text><!-- accelerator --><path d="M120,138 L160,150" stroke="#38bdf8" stroke-width="1.5"/><rect x="150" y="146" width="6" height="12" fill="#38bdf8"/><rect x="162" y="150" width="6" height="12" fill="#38bdf8"/><text x="168" y="140" fill="#38bdf8" font-size="6.5">accelerate</text><!-- beam to wafer --><line x1="168" y1="158" x2="200" y2="170" stroke="#34d399" stroke-width="2"/><polygon points="197,166 203,169 197,174" fill="#34d399"/><!-- wafer --><rect x="188" y="176" width="24" height="60" rx="2" fill="#38506a"/><text x="200" y="250" fill="#cfe4f5" font-size="7" text-anchor="middle">wafer</text><text x="52" y="264" fill="#8b949e" font-size="7">beam is scanned to cover the whole wafer</text><text x="32" y="288" fill="#adb5bd" font-size="9.5">A source ionizes the dopant; a magnet</text><text x="32" y="303" fill="#adb5bd" font-size="9.5">bends the beam to select one species and</text><text x="32" y="318" fill="#adb5bd" font-size="9.5">mass; high voltage accelerates it; the</text><text x="32" y="333" fill="#adb5bd" font-size="9.5">beam is scanned across the wafer. The</text><text x="32" y="348" fill="#adb5bd" font-size="9.5">measured beam current gives exact dose.</text><!-- Panel 2: the profile --><rect x="267" y="66" width="226" height="298" rx="7" fill="#0c141d" stroke="#30363d"/><text x="279" y="88" fill="#9fd8ef" font-size="13" font-weight="700">2 &#183; Where the ions stop</text><text x="279" y="106" fill="#8b949e" font-size="10.5">energy sets depth, dose sets amount</text><rect x="287" y="118" width="196" height="128" rx="3" fill="#111a24" stroke="#30363d"/><!-- incoming ions --><g stroke="#34d399" stroke-width="1.2"><line x1="300" y1="126" x2="300" y2="140"/><line x1="316" y1="126" x2="316" y2="140"/><line x1="332" y1="126" x2="332" y2="140"/></g><!-- mask blocking part --><rect x="350" y="132" width="120" height="10" fill="#e0b13a"/><text x="410" y="140" fill="#0d1117" font-size="7" text-anchor="middle">mask blocks</text><!-- silicon --><rect x="295" y="142" width="180" height="96" fill="#1c2733"/><!-- implanted gaussian region under opening --><path d="M300,150 Q318,150 318,175 Q318,200 300,205 Z" fill="#34d399" opacity="0.35"/><ellipse cx="315" cy="180" rx="16" ry="20" fill="#34d399" opacity="0.4"/><text x="300" y="230" fill="#34d399" font-size="7">peak at projected range Rp</text><!-- depth axis --><line x1="345" y1="150" x2="345" y2="232" stroke="#8b949e" stroke-width="0.8"/><text x="349" y="158" fill="#8b949e" font-size="6.5">shallow (low E)</text><text x="349" y="228" fill="#8b949e" font-size="6.5">deep (high E)</text><text x="279" y="266" fill="#adb5bd" font-size="9.5">Ions plow in and stop at a depth set by</text><text x="279" y="281" fill="#adb5bd" font-size="9.5">energy, leaving a buried concentration</text><text x="279" y="296" fill="#adb5bd" font-size="9.5">peak. Dose (ions/cm&#178;) sets how many;</text><text x="279" y="311" fill="#adb5bd" font-size="9.5">the mask defines exactly which regions</text><text x="279" y="326" fill="#adb5bd" font-size="9.5">get doped &#8212; source, drain, wells and Vt</text><text x="279" y="341" fill="#adb5bd" font-size="9.5">adjust implants are all separate steps.</text><!-- Panel 3: damage & anneal --><rect x="514" y="66" width="226" height="298" rx="7" fill="#0c141d" stroke="#30363d"/><text x="526" y="88" fill="#c4b5fd" font-size="13" font-weight="700">3 &#183; Damage, then anneal</text><text x="526" y="106" fill="#8b949e" font-size="10.5">implant breaks the lattice; heat heals it</text><circle cx="532" cy="126" r="2.4" fill="#f87171"/><text x="542" y="129" fill="#e6edf3" font-size="10" font-weight="700">Implant damages silicon</text><text x="542" y="143" fill="#8b949e" font-size="9">crashing ions knock atoms off lattice</text><text x="542" y="156" fill="#8b949e" font-size="9">sites; the dopants aren&#8217;t active yet.</text><circle cx="532" cy="176" r="2.4" fill="#e0b13a"/><text x="542" y="179" fill="#e6edf3" font-size="10" font-weight="700">Anneal activates &amp; repairs</text><text x="542" y="193" fill="#8b949e" font-size="9">a rapid thermal anneal repairs the crystal</text><text x="542" y="206" fill="#8b949e" font-size="9">and moves dopants onto lattice sites.</text><circle cx="532" cy="226" r="2.4" fill="#38bdf8"/><text x="542" y="229" fill="#e6edf3" font-size="10" font-weight="700">Keep junctions shallow</text><text x="542" y="243" fill="#8b949e" font-size="9">too much heat diffuses dopants and blurs</text><text x="542" y="256" fill="#8b949e" font-size="9">the junction &#8212; spike anneals limit spread.</text><rect x="526" y="272" width="202" height="82" rx="5" fill="#111a24" stroke="#30363d"/><text x="536" y="290" fill="#7ee6c0" font-size="10" font-weight="700">Precision doping, by design</text><text x="536" y="306" fill="#adb5bd" font-size="9">Unlike diffusion from a gas, implant sets</text><text x="536" y="320" fill="#adb5bd" font-size="9">dose and depth independently and exactly.</text><text x="536" y="334" fill="#adb5bd" font-size="9">That control is why every modern transistor&#8217;s</text><text x="536" y="348" fill="#adb5bd" font-size="9">doping profile is built by ion implantation.</text><!-- bottom cards --><rect x="20" y="384" width="226" height="70" rx="7" fill="#111a24" stroke="#30363d"/><text x="32" y="406" fill="#34d399" font-size="11" font-weight="700">Dose &amp; energy</text><text x="32" y="424" fill="#adb5bd" font-size="9.5">Dose sets how many dopants, energy</text><text x="32" y="440" fill="#adb5bd" font-size="9.5">sets how deep &#8212; set independently.</text><rect x="267" y="384" width="226" height="70" rx="7" fill="#111a24" stroke="#30363d"/><text x="279" y="406" fill="#e0b13a" font-size="11" font-weight="700">Mask defines where</text><text x="279" y="424" fill="#adb5bd" font-size="9.5">Resist blocks the beam, so only the</text><text x="279" y="440" fill="#adb5bd" font-size="9.5">open regions get doped.</text><rect x="514" y="384" width="226" height="70" rx="7" fill="#111a24" stroke="#30363d"/><text x="526" y="406" fill="#38bdf8" font-size="11" font-weight="700">Anneal to activate</text><text x="526" y="424" fill="#adb5bd" font-size="9.5">Heat repairs the lattice and turns the</text><text x="526" y="440" fill="#adb5bd" font-size="9.5">implanted atoms into active dopants.</text></svg>

An ion implantation chamber is the vacuum system where dopant ions are accelerated and directed into the semiconductor wafer to modify its electrical properties. Vacuum: Maintained at 10^-5 to 10^-7 Torr to prevent ion scattering by gas molecules and maintain beam purity. Major components: Ion source, mass analyzer magnet, acceleration column, beam scanning system, wafer handling end station. Beam path: Ions extracted from source, filtered by mass analyzer, accelerated to target energy, scanned across wafer. End station: Where wafer is held during implantation. Includes wafer chuck (cooled or heated), Faraday cup for dose measurement, charge neutralization. Dose control: Beam current measured in real-time by Faraday cup. Total dose controlled by integrating current over time. Uniformity: Beam scanned across wafer (electrostatic or mechanical scanning) for uniform dose distribution. Types: Beamline: Traditional architecture with mass analyzer and acceleration tube. Plasma immersion (PLAD): Wafer immersed in plasma, ions extracted by pulsed bias. Higher throughput for high-dose implants. Energy range: Low energy (0.2-10 keV) for shallow junctions. Medium (10-200 keV) for wells. High (200 keV - several MeV) for deep implants. Safety: High voltage, radiation, toxic gases (AsH3, PH3, BF3) require extensive safety systems.