tcad simulation of the mupix7 sensor for the mu3e pixel
TRANSCRIPT
TCAD Simulation of the MuPix7 Sensor for theMu3e Pixel Tracker
Annie Meneses Gonzalez
Physikalisches Institut Heidelberg
DPG Spring MeetingMarch 19, 2018
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 1 / 17
Outline
• The Mu3e Experiment∗ Goal∗ Challenges
• TCAD Simulation
∗ Motivation∗ Synopsis Sentaurus Software∗ Device Structure (MuPix7)∗ Simulation of quasi-stationary characteristics∗ Transient simulation of MIP
• Summary
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 2 / 17
The Mu3e Experiment
Decay µ→eee mediated by neutrino mixing
BR (µ+ → e+e−e+)10−54→StandardModel
• Too small to access experimentally
• An experimental observation: a clearsignature of new Physics
Search for Physics Beyond SMvia the Charged Lepton FlavorViolation decay
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 3 / 17
Challenges of the Experiment
1. High decay rate of muon• πE5 at PSI⇒ 108 Hz Phase I⇒ 290 days of data taking• 109 Hz Phase II (possibility under investigation at PSI)
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 4 / 17
Challenges of the Experiment
1. High decay rate of muon• πE5 at PSI⇒ 108 Hz Phase I⇒ 290 days of data taking• 109 Hz Phase II (possibility under investigation at PSI)
Two categories of background
Accidental Background Irreducible Background
2. Good vertex and timing resolution⇒ 100 µm and 500 ps
3. Excellent momentum resolution⇒ 0.5 MeV
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 5 / 17
High Voltage Monolithic Active Pixel Sensors
• Low momenta decay electrons⇒ up to 53 MeV• Multiple Coulomb scattering
Pixel tracker based on 50 µm thin HV-MAPS
∗ Integration of sensor andreadout functionalities⇒ Reduce material budget
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 6 / 17
Technology Computer Aided Design
• MAPS reversely biased to highvoltages
• Thick depleted area⇒ 15 µm for 20 Ωcm
• Fast time collection via drift⇒ time resolution better than 15 ns
TCADUse of computer simulations to develop and optimize semiconductorprocessing technologies and devices
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 7 / 17
Synopsys Sentaurus TCAD
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 8 / 17
MuPix7• First HV-MAPS prototype which include all the
funtionalities required for the Mu3e experiment
Pixel size [µm2] 103 x 80Bulk resistance [Ωcm] 20Active area [mm2] 10.6Thickness [µm] 50 Layout of the MuPix7 pixel unit cell
with nine charge collecting diodesand the in-pixel circuitryExperimental results:
∗ DESY-II beam test facility∗ EUDET Telescope⇒MAPS MIMOSA-26
∗ 4 GeV electron beam
https://arxiv.org/abs/1803.01581
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 9 / 17
Creation of the Structure
1. Accurate prediction of the geometry and doping distribution
Build mesh distribution
2. Simulation of quasi-stationary characteristics
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 10 / 17
Quasi-stationary characteristics
• Electric Field profile
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 11 / 17
Signal generation from Minimum Ionizing Particles
• Energy loss⇒ 5 MeV/cm
• Electron beam⇒ 4 GeV
• Ionization Energy⇒ Silicon 3.6 eV
Linear Energy Transfer
⇒ 2×10−5 pC/µm
⇒ 130 e− h/µm
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 12 / 17
Signal generation from Minimum Ionizing Particles
• Fit function
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 13 / 17
Charge collection time
Bias Voltage⇒ -40 V
• Edge of the pixel⇒ Charge sharing
• Between diodes⇒ Not fully depleted⇒ Lost by recombination⇒ Collected via diffusion
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 14 / 17
Charge collection time
Bias Voltage⇒ -40 V
• Edge of the pixel⇒ Charge sharing
• Between diodes⇒ Not fully depleted⇒ Lost by recombination⇒ Collected via diffusion
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 15 / 17
Charge collection time
Bias Voltage⇒ -85 V
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 16 / 17
Summary
• The structure and collection process of MuPix7 was reproduced.
• Taking into account the limited position resolution of themeasurement, all major features are reproduced by the simulation.
• Simulation can be used to further optimize the charge collectionprocess and timing behavior in future devices.
Annie Meneses Gonzalez [email protected] Physikalisches Institut Heidelberg
TCAD Simulation of the MuPix7 Sensor for the Mu3e Pixel Tracker 17 / 17