Dynamic Adjustment of Electrostatic Adsorption Power Supply Force and Adaptation to Surface Microstructure

Electrostatic adsorption power supplies are widely used in semiconductor wafer handling, precision optical substrate fixation, and flexible display manufacturing. Their core function is to generate a controlled electrostatic field between the electrode and target surface, providing a non-contact holding force. The magnitude and uniformity of this adsorption force are determined by the output characteristics of the power supply and the microstructure of the contact surface. Traditional systems operate at fixed voltage levels, leading to inconsistent adsorption performance when handling materials with varying dielectric constants or surface roughness.
To address this, an adaptive electrostatic adsorption power supply has been developed that integrates dynamic force control and surface-structure-based optimization. The system features multi-zone high-voltage outputs, each independently regulated through closed-loop feedback. Capacitance sensing circuits embedded in each zone continuously measure changes in the dielectric gap and surface topology. These data are processed using an adaptive fuzzy-PID control algorithm to modulate the output voltage of each zone, thereby maintaining a uniform electrostatic field across uneven or porous surfaces.
The power supply also incorporates high-frequency alternating-polarity modulation to reduce residual charge accumulation, which can lead to particle contamination or surface damage. By adjusting both frequency and duty cycle dynamically, the system optimizes the penetration depth of the electric field according to material dielectric properties.
For applications involving micro-rough or patterned surfaces, a phase-controlled voltage waveform is used to match local field intensity to microstructural geometry. Advanced digital control using FPGA-based timing synchronization enables sub-millisecond voltage transitions, minimizing electric field overshoot and ensuring stable adsorption during rapid motion or thermal cycling.
Real-time feedback from force sensors or interferometric displacement detectors allows continuous monitoring of actual adsorption performance. The control unit compensates for environmental changes such as humidity or temperature by adjusting the electrostatic potential accordingly. With integrated predictive algorithms, the system can anticipate detachment risks and preemptively adjust the field distribution to maintain stability. This adaptive and intelligent regulation enhances process reliability and energy efficiency in high-precision electrostatic clamping applications.