Ultra-High-Frequency Resonant Voltage Stabilization Technology for Lithography Machine High-Voltage Power Supplies

In semiconductor manufacturing, lithography machines are core equipment for nanoscale pattern etching, where precision directly determines chip performance and yield. The high-voltage power system of a lithography machine must provide ultra-stable electrical energy for critical components such as laser generators and ion beam controllers. Ultra-high-frequency resonant voltage stabilization technology (frequency range: 1–10 MHz) has emerged as a key innovation to overcome the limitations of traditional power supplies. 
1. Technical Challenges of Ultra-High-Frequency Resonant Stabilization
Lithography machines impose near-extreme demands on power stability: 
1. Ultra-low voltage fluctuation tolerance: Exposure precision requires nanoscale control, necessitating output voltage fluctuations ≤ ±0.1% and total harmonic distortion (THD) < 1%. 
2. Suppression of ultra-high-frequency noise: Resonant noise at 1–10 MHz generated during power device switching couples to the output through parasitic capacitance and inductance, causing pattern distortion. 
3. Dynamic response speed: Voltage must stabilize within 10ms during load transients to maintain wafer alignment precision. 
Traditional linear regulators fail due to low efficiency and thermal challenges, while switching power supplies introduce high-frequency ripple as a new bottleneck. 
2. Core Principles of Ultra-High-Frequency Resonant Stabilization
This technology leverages LC series resonant topology (Figure 1) to achieve high-efficiency voltage stabilization through electromagnetic energy oscillation: 
• Adaptive resonant point tracking: Inductor (L) and capacitor (C) parameters are designed so the resonant frequency  f_r = \frac{1}{2\pi\sqrt{LC}}  matches the lithography machine's operating band. At resonance, system impedance minimizes and current maximizes, enabling efficient energy transfer. 
• Dual-loop control strategy: 
  • Outer voltage loop: Real-time output voltage sampling generates frequency commands via a PI controller; 
  • Inner frequency modulation: DSP-based algorithms dynamically adjust PWM frequency to maintain operation near resonance, compressing voltage fluctuations to within ±0.05%. 
• Common-mode noise suppression: A dual-layer shield structure—inner permalloy magnetic shield blocks low-frequency fields, while outer copper mesh suppresses high-frequency EMI—attenuates conducted noise by ≥40dB. 
3. Key Technological Breakthroughs
1. Soft-recovery diodes & low junction capacitance devices 
   Ultrafast recovery diodes (reverse recovery time <50ns) and gallium nitride (GaN) power devices reduce switching losses by 60% and suppress ultra-high-frequency resonant noise. 
2. Temperature-frequency cooperative compensation 
   LC parameter drift due to temperature requires embedded sensors and compensation algorithms: 
    f_{r\_adj} = f_r \cdot \left[1 + \alpha(T T_0)\right]  
   where α is the temperature coefficient, T is real-time temperature, and T0 is the reference temperature. This design reduces thermal drift impact to 0.001%/°C. 
3. Distributed filtering architecture 
   • Front stage: Active filters suppress low-frequency ripple (<100kHz); 
   • Rear stage: π-type filter combinations (LC+RC) eliminate noise >1MHz, achieving output ripple <10mVpp. 
4. Application Efficacy and Future Prospects
Tests in a 7nm EUV lithography machine demonstrated: 
• 18% improvement in exposure precision, with pattern linewidth error ≤1.2nm; 
• Ion beam energy fluctuation reduced from ±0.5% to ±0.08%, boosting chip yield to >95%. 
Future advancements will integrate wide-bandgap semiconductors to push operating frequencies beyond 20MHz, delivering zero-interference power cores for 2nm and below process nodes.