Digital Drive Solution for High-Voltage Power Supply in Lithography Exposure Machines: Technical Application and Performance Enhancement

In the lithography process of semiconductor manufacturing, the imaging accuracy of lithography exposure machines directly determines the chip process level. As the core component for energy supply and optical system operation of exposure machines, the high-voltage power supply (HVPS) has its output stability, accuracy, and dynamic response capability as key factors restricting the exposure process indicators. Traditional HVPS for exposure machines mostly adopts an analog drive architecture, relying on control circuits composed of discrete components. It has problems such as delayed parameter adjustment, sensitivity to temperature drift, and weak ripple suppression capability, which makes it difficult to meet the strict requirements of advanced processes below 7nm for voltage control accuracy (required to be ≤0.05%) and dynamic response speed (required to be ≤1μs). Therefore, the digital drive solution for HVPS, by integrating digital control, high-precision sampling, and intelligent algorithms, has become a core path to break through the bottlenecks of traditional technologies.
The core of the digital drive solution lies in constructing a full-digital closed-loop system of control-sampling-feedback-optimization. In terms of the control architecture, a dual-core processing mode of FPGA + MCU is adopted: the FPGA is responsible for the real-time generation of the HVPS output waveform and the precise output of high-frequency pulse-width modulation (PWM) signals. Its parallel processing capability can control the execution delay of voltage adjustment commands within the nanosecond level; the MCU undertakes tasks such as system parameter configuration, status monitoring, and communication interaction. It realizes coordination with the main control system of the exposure machine through a standardized digital interface, avoiding interference problems in analog signal transmission. Compared with traditional analog control, this architecture can flexibly adjust control algorithms through software iteration, and adapt to the voltage requirements of different exposure modes (such as deep ultraviolet exposure and extreme ultraviolet exposure) without replacing hardware, significantly improving the solution compatibility.
High-precision sampling and dynamic feedback are the performance guarantees of the digital solution. The solution uses a 16-bit high-speed ADC (sampling rate ≥1MSps) for synchronous collection of output voltage and current. Combined with digital filtering algorithms (such as Kalman filtering), it eliminates noise caused by power grid fluctuations and load changes, ensuring a sampling error of ≤0.01%. At the same time, the feedback mechanism based on model predictive control (MPC) can real-time analyze the deviation between the sampled data and the target voltage, and dynamically adjust the PWM duty cycle. This shortens the voltage recovery time of the power supply to less than 500ns when the load changes suddenly (such as exposure beam switching), and the ripple rejection ratio (RRR) is increased to more than 80dB, which is much higher than the 65dB level of traditional analog solutions.
In addition, the digital solution also integrates intelligent management functions: by real-time monitoring key parameters of the power module such as temperature, humidity, and insulation resistance, a fault early warning model is built, which can predict potential faults (such as insulation aging and component overheating) 200ms in advance, reducing the shutdown risk of the exposure machine. At the same time, based on the digital energy efficiency algorithm, the power supply output power is dynamically adjusted according to the energy demand of the exposure process, reducing energy consumption by 15%~20%, which conforms to the green production trend of semiconductor manufacturing.
From the perspective of application practice, the digital drive solution for HVPS in exposure machines has realized the transformation from passive adjustment to active optimization. Its voltage control accuracy can reach ±0.03%, and the dynamic response speed meets the exposure rhythm requirements of advanced processes. This solution not only solves the technical pain points of traditional analog drives, but also provides core support for the performance upgrade of semiconductor lithography equipment through the in-depth integration of digital technology and exposure processes, promoting the development of chip manufacturing towards higher precision and higher efficiency.