Speaker
Description
After LHC Upgrade II at CERN, LHCb aims to run at an instantaneous luminosity of $1.5 \times 10^{34}/cm^2/s$ and a total integrated luminosity of $300 fb^{-1}$. To support this high-luminosity operation, upgrades are planned for the LHCb detectors, including the downstream tracker, known as the Mighty Tracker. One of the key upgrades is the introduction of silicon pixel detectors, called MightyPix, into the central region of the Mighty Tracker. We have developed prototype chips for MightyPix based on the HV-MAPS (High Voltage Monolithic Active Pixel Sensors) design fabricated using a commercially available CMOS process on high-resistivity wafers. This approach enables the large-scale production of the high hit-rate capable (~ $32 Mhits/cm^2$), radiation hard (NIEL of $3 \times 10^{14}n_{eq}/cm^2$, TID of 40Mrad) pixel detectors required by the Mighty Tracker.
LF-MightyPix has been fabricated as a second prototype chip, using a different foundry than the first and upcoming third prototype chip. This serves to evaluate the feasibility of using an alternative foundry without impacting the overall project. The chip size of LF-MightyPix is $3.3 mm \times 4 mm$ with a pixel pitch of $100 \mu m \times 100\mu m$. For each hit, both the time of arrival and the time over threshold are recorded to ensure correct bunch crossing identification at 40 MHz. In addition to demonstrating foundry compatibility, the chip has implemented digital interfaces and protocols tailored to the LHCb DAQ/Control system, e.g., 1.28Gbps data rate with DC-balanced encoding and “Timing and Fast Control” interface.
In this presentation, we will report on the performance of the LF-MightyPix evaluated both electrically and using particles. We will also outline the development plan of MightyPix, including the next prototype chip.
