Capacitance extraction for Medipixlike Sensor using TCAD Simulation

Capacitance extraction for Medipixlike Sensor using TCAD Simulation Mathieu Benoit

Introduction • Goal : Predict Noise in Medipix 3 RX Microns n-in-p assemblies using Capacitance predicted using TCAD Simulation • Method : – Create a 3 D model in TCAD of a Micron sensor, using mask and process simulation – Perform DC and AC simulation to extract Capacitance vs Frequency curve between each node of the model

Process Flow TCAD Simulation • Process flow is a method using GDS production files to simulate the fab process flow and generate a realistic structure for Electrical simulation • I wrote a generic GDSII Pixel mask generator that allow to draw realistic mask for various geometries

Python GDSII Generator • You specify: – – – Pitch Implant/Al width Passivation opening width Contact to implant width Guard Ring Dimensions Full Timepix Matrix + GR 3 x 3 CLICPix Sensor 3 x 3 Timepix Sensor

Process Flow Simulation

Process Flow Simulation + =

Pixel Profile after full process Simulation P-Spray Al N+

Next Step • I have a fully simulated single pixel, after input of Micron, I will generate a 3 x 3 model • From the 3 x 3 model I will extract : – Interpixel Capacitance vs Frequency (what frequency ? ) – Pixel-Backside Capacitance • Using GDSII python generator, we can generate many variation on the geometry to compare Capacitance results • Possibility to add Bumps and ASIC Using Sentaurus Interconnect