First insights on super-gq DePFET: An improved high performance sensor with increased gain and sub-electron noise levels capabilities

DePFET (Depleted P-channel Field Effect Transistor) sensors have already demonstrated impressive readout noise levels, of around 2 e- ENC at a speed of 5 μs per line. Recent development efforts suggest that adding an n-implant to the source side of the device can significantly further improve the signal-to-noise ratio (SNR). This approach, the so-called super-gq DePFET technology confines the internal gate to a small area beneath the channel, essentially decoupling the internal and external gate sizes. Simulations indicate that this modification can increase the charge gain by a factor of three (to 1.7 nA/e-) and reduce the white noise to less than 1 e- ENC, while also mitigating impact ionization near the drain end of the channel. Recent test productions of super-gq DePFETs have been completed, and initial measurements provide first insights into the device transfer characteristics, alignment with simulations and confirmation of the operational viability of this concept.