We have been developing a new type of X-ray pixel sensors, “XRPIX”, allowing us to perform imaging spectroscopy in the wide energy band of 1–20$\mathrm{keV}$ for the future Japanese X-ray satellite “FORCE”. The XRPIX devices are fabricated with complementary metal-oxide-semiconductor silicon-on-insulator technology, and have the “Event-Driven readout mode”, in which only a hit event is read out by using hit information from a trigger output function equipped with each pixel. This paper reports on the low-energy X-ray performance of the “XRPIX6E” device with a Pinned Depleted Diode (PDD) structure. The PDD structure especially reduces the readout noise, and hence is expected to largely improve the quantum efficiencies for low-energy X-rays. While F-K X-rays at $0.68\mathrm{keV}$ and Al-K X-rays at $1.5\mathrm{keV}$ are successfully detected in the “Frame readout mode”, in which all pixels are read out serially without using the trigger output function, the device is able to detect Al-K X-rays, but not F-K X-rays in the Event-Driven readout mode. Non-uniformity is observed in the counts maps of Al-K X-rays in the Event-Driven readout mode, which is due to region-to-region variation of the pedestal voltages at the input to the comparator circuit. The lowest available threshold energy is $1.1\mathrm{keV}$ for a small region in the device where the non-uniformity is minimized. The noise of the charge sensitive amplifier at the sense node and the noise related to the trigger output function are $\sim$ $18e^{-}$ (rms) and $\sim$ $13e^{-}$ (rms), respectively.

我们正在开发一种新型的X射线像素传感器“ XRPIX”，使我们能够在1–20的宽能带中执行成像光谱$\mathrm{keV}$为未来的日本X射线卫星“ FORCE”。XRPIX器件采用互补金属氧化物半导体绝缘体上硅技术制造，并具有“事件驱动的读出模式”，在该模式下，使用配备有触发输出功能的命中信息只能读出命中事件每个像素。本文报告了具有固定耗尽二极管（PDD）结构的“ XRPIX6E”设备的低能X射线性能。PDD结构尤其减少了读出噪声，因此有望大大提高低能X射线的量子效率。当FK X射线在$0。68\mathrm{keV}$ 和Al-K X射线在 $\mathrm{1个}。5\mathrm{keV}$在“帧读取模式”下成功检测到图像，在该模式下，无需使用触发输出功能即可连续读取所有像素，该设备能够检测事件驱动的Al-K X射线，但不能检测FK X射线读出模式。在事件驱动的读出模式下，在Al-K X射线的计数图中观察到不均匀性，这是由于比较器电路输入端的基座电压在区域间变化所致。最低可用阈值能量为$\mathrm{1个}。\mathrm{1个}\mathrm{keV}$对于设备中不均匀性最小的小区域。感应节点处的电荷敏感放大器的噪声和与触发输出功能有关的噪声为$〜$ $\mathrm{18岁}{Ë}^{-}$ （rms）和 $〜$ $13{Ë}^{-}$ （rms）。