Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Performance of USTC first batch resistive AC-LGAD sensor

Han Li, Xiao Yang, Kuo Ma, Hang Yang, Aonan Wang, De Zhang, Tianao Wang, Xiangxuan Zheng, Jiajin Ge, Yusheng Wu, Hao Liang, Yanwen Liu

Abstract

In this paper, the design and characterization of AC-LGAD sensors at the University of Science and Technology of China is introduced. The sensors are characterized with an infrared laser Transient Current Technique (TCT) system for evaluating signal response characteristics and spatial resolution. The temporal resolution was quantified with electrons emitted by a Sr-90 radioactive source. The spatial resolution can reach 4 μm and a temporal resolution of 48 ps is achieved

Performance of USTC first batch resistive AC-LGAD sensor

Abstract

In this paper, the design and characterization of AC-LGAD sensors at the University of Science and Technology of China is introduced. The sensors are characterized with an infrared laser Transient Current Technique (TCT) system for evaluating signal response characteristics and spatial resolution. The temporal resolution was quantified with electrons emitted by a Sr-90 radioactive source. The spatial resolution can reach 4 μm and a temporal resolution of 48 ps is achieved

Paper Structure

This paper contains 9 sections, 4 equations, 12 figures.

Table of Contents

  1. Introduction
  2. Design and fabrication of USTC 1st batch AC-LGAD
  3. Sensor characteristics
  4. Static characteristics
  5. Dynamical properties
  6. Spatial and temporal resolution
  7. Spatial resolution
  8. Temporal resolution
  9. Conclusion

Figures (12)

  • Figure 1: Cross-section of an AC-LGAD device (not-to-scale). From the device physical edge to the center: Guard-Ring, P-stop, JTE, P-well region with AC electrode on top. With a continuous gain layer, the fill-factor issue of DC-LGAD is solved. A dielectric layer between the gain layer and the readout electrode is deposited to achieve the AC-coupled readout.
  • Figure 2: The electric field and potential distribution inside a 50 $\mu$m thick AC-LGAD sensor from the process simulation with a certain process parameter. The structures on the top layer from the edge to the center are: guard ring, DC contact, readout electrodes on top of the gain layer.
  • Figure 3: (a) A $2\times2$ pad array setup in CST suite. The pad size is 50 $\mu$m $\times$ 50 $\mu$m and the pitch size is 300 $\mu$m $\times$ 300 $\mu$m. Virtual pins are created on the readout pads to connect to the amplifiers. Another pin to inject the source current representing the drifting charge carriers. (b) the waveforms observed on the four pads when a source current is injected near the upper right corner as indicated in (a).
  • Figure 4: A photo of the USTC AC-LGAD showing the electrode layout of the device (left) and the geometrical parameters of different electrode types: Pad and Strip. The electrode pitch, electrode width, and the numbers of electrodes in column and row directions are summarized (right).
  • Figure 5: IV and CV curves of the AC-LGAD sensors fabricated at USTC. These samples come from different positions on two wafers while W represents the wafer label and P represents the position label.
  • ...and 7 more figures