Single Photon Detection: Advanced DePFET with High Amplification
Sensors, Devices and Components
- Simple to manufacture extension to the well proven DePFET concept
- Quicker and less losses than in CCD detectors
- Single photon detection possible
- Increased amplification by a factor of 5 compared to other DePFET detectors
- Transistor current of more than 2 nA per signal electron
- Single Photon detection
- X-Ray imaging
- Industrial quality inspections
- High energy physics, Particle detectors
DePFETs are well known components used in detector assemblies since decades as they possess high intrinsic charge amplification combined with low noise levels resulting in excellent SNR values. The charge multiplication however is limited by the geometry of the internal gate. A further improved gain would be favorable for various detector applications, but an even smaller gate size would lead to higher electric fields and thus increased noise, making this approach inappropriate.
An advancement of the current DePFET principle has been developed to overcome the aforementioned shortcomings and to further expand the application possibilities of DePFET detectors.
As the fundamental constraint is purely a result from the high potential drop over small distances for improved internal gate geometries, the invention is based on the use of additional implants over which a portion of the Drain-Source-Voltage can drop. This allows to reduce the internal gate length significantly and hence improve the amplification.
A possible implementation of the invention can be seen in figure 2. Within the main substrate (100), limited by its two surfaces (101, 102), it comprises the drain and the source terminal (1d, 1s), as well as a doping increased region (2) and the channel region (10). The latter is located beneath the gate electrode (11) and the gate insulator (6). The rear activation region (104) is located on the opposite side.
According to the invention, the key component used to reduce the internal gate size is the additional n-implant (20) which localizes the internal gate and decouples its size from the one of the external gate without increasing the detector noise.
PCT (WO2020225275A1), EPO (EP3942619A1), DPMA (DE102019206494A1)
A. Bähr, et al., " Advanced DePFET concepts: super gq DePFET", Proc. of SPIE Vol. 11454 (2020).
- Ref.-No.: 1201-5766-BC (372.2 KiB)
Dr. Bernd Ctortecka, M. Phil.
Phone: +49 89 / 29 09 19-20