A New Method for Precisely Designing the Spiral Structure of an SDD with Optimal Electrical Properties

Area of Science:

• Semiconductor Device Physics
• Detector Technology
• Applied Electromagnetics

Background:

• Silicon Drift Detectors (SDDs) are crucial for high-resolution radiation detection.
• Accurate calculation of spiral electrode geometry is vital for optimal SDD performance.
• Existing methods for calculating spiral dimensions in SDDs lack sufficient precision.

Purpose of the Study:

• To develop a more accurate method for calculating the spiral electrode radius and number of turns in SDDs.
• To improve the precision of single-sided hexagonal spiral SDD fabrication.
• To enhance the electrical performance of SDDs through optimized spiral geometry.

Main Methods:

• Utilizing Taylor expansion to derive first- and second-order approximations of differentiation equations for the spiral angle.
• Integrating derived approximations with formulas for electrode pitch P(r) and width W(r).
• Developing a physically intuitive method for high-precision spiral SDD design.

Main Results:

• The second-order approximation yields a greater number of spiral turns compared to the first-order approximation.
• Optimized spiral geometry results in smoother electric potential profiles.
• Improved electric field distributions and more-defined electron drift channels are achieved.

Conclusions:

• The proposed method enhances the accuracy of spiral electrode calculations in SDDs.
• Second-order approximation leads to superior electrical performance in spiral SDDs.
• This work provides a simple and effective approach for designing high-performance SDDs.