Novel Spiral Silicon Drift Detector with Equal Cathode Ring Gap and Given Surface Electric Fields.

Area of Science:

• Semiconductor Physics
• Detector Technology
• Materials Science

Background:

• Semiconductor detectors have undergone continuous development and performance improvements over generations.
• Traditional spiral silicon drift detectors (SDDs) feature a cathode ring gap that increases with radius.
• This traditional structure presents limitations in surface electric field control and leakage current.

Purpose of the Study:

• To propose and investigate a novel spiral silicon drift detector (SDD) structure.
• To enhance detector performance by optimizing the cathode ring gap and surface electric field.
• To reduce surface leakage current and improve carrier drift characteristics.

Main Methods:

• Development of a new spiral SDD structure with an equal cathode ring gap.
• Modeling and simulation of the proposed structure's electrical properties using Sentaurus TCAD.
• Analysis and comparison of various cathode ring gap sizes (10 µm to 25 µm).

Main Results:

• The novel SDD structure controllably reduces the silicon oxide area between spiral rings.
• A 10 µm cathode ring gap demonstrated superior electrical characteristics, including uniform potential and electric field distribution.
• The optimal gap resulted in a smoother, straighter electron drift channel.

Conclusions:

• The proposed spiral SDD structure with an equal cathode ring gap offers significant advantages over traditional designs.
• This design effectively reduces surface leakage current by minimizing oxide charge and interface states.
• Optimized electric field distribution leads to enhanced carrier drift and improved overall detector performance.