The design and evaluation on the NSLS-II beamline of the 3FI application specific integrated circuit (ASIC) bump-bonded to a simply, planar, two-dimensionally segmented silicon sensor is presented. The ASIC was developed for Full-Field Fluorescence spectral X-ray Imaging (3FI). It is a small-scale prototype that features a square array of 32x32 pixels with a pitch of 100 μm. The ASIC was implemented in a 65 nm CMOS process. Each pixel incorporates a charge-sensitive amplifier, shaping filter, discriminator, peak detector, and sample-and-hold circuit, allowing detection of events and storing signal amplitudes. The system operates in an event-driven readout mode, outputting analog values for threshold-triggered events, allowing high-speed multi-element X-ray fluorescence imaging. At power consumption of 200 μW per pixel, consisting almost uniquely of power dissipated in analog blocks, 308 eV full width at half maximum (FWHM) energy resolution at 8.04 keV, that corresponds to 30 e- rms equivalent noise charge (ENC) and 138 eV FWHM energy resolution at 3.69 keV (16 e- rms ENC) were obtained, for Cu and Ca Kα lines, respectively. Each pixel operates independently, and the detector enables in situ trace element microanalysis in biological and environmental research. Its architecture addresses limitations of X-ray Fluorescence Microscopy (XFM), typically requiring mechanical scanning, by offering frame-lees data acquisition, translating to high-throughput operation. The 3FI ASIC is suitable for example for studies of nutrient cycling in the (mycor)rhizosphere, microbial redox processes, and genotype-phenotype correlations in bio-energy crops. Additional performances, such as enhanced spatial resolution can be further improved with coded-aperture and Wolt, extending the use to environmental, biomedical, and material science studies.
Monolithic arrays of silicon p-n junctions are commonly used to deliver spatial information on impinging radiation, with the advantages of low-noise and fast signal generation. Additionally, array geometries also allow for a segmentation of a large area into individual channels that can be read out in parallel, so that a high-event rate can be managed. To optimize the noise performance, however, some key points must be addressed to control the silicon/silicon oxide interface. Replacing the p-n junctions with silicon drift sensors avoids noise related to the interface states, at the expense of a more complicated process and slower signals. In this paper, some of the aspects needing consideration when engineering a monolithic array of silicon sensors are reviewed.
We developed a new front-end application specific integrated circuit (ASIC) for the upgrade of the Maia x-ray microprobe. The ASIC instruments 32 configurable front-end channels that perform either positive or negative charge amplification, pulse shaping, peak amplitude and time extraction along with buffered analog storage. At a gain of 3.6 V/fC, 1 $\mu$s peaking time and a temperature of 248 K, an electronic resolution of 13- and 10 electrons rms was measured with and without a SDD sensor respectively. A spectral resolution of 170 eV FWHM at 5.9 keV was obtained with an $^{55}$Fe source. The channel linearity was better than $\pm$ 1 % with rate capabilities up to 40 kcps. The ASIC was fabricated in a commercial 250 nm process with a footprint of 6.3 mm x 3.9 mm and dissipates 167 mW of static power.
Arrays of silicon sensors can be used in those spectroscopic applications where a high event throughput is needed, for example, in synchrotron-based experiments. However, in such arrays, several noise contributions, beyond the well-known leakage, thermal, and flicker noises, can be present, which are absent in single-channel detectors. Additional noise is generated ultimately by the condition at the silicon/silicon-oxide interface, which in turn depends on the parameters of the silicon oxide over the not-implanted gaps. We discuss how to control this region to obtain the best spectroscopic performances.
We present a low-power, low-noise prototype pixel readout application specific integrated circuit (ASIC) for hyperspectral energy-resolving X-ray imaging detectors. The ASIC provides 16-by-16 channels to read out positive and negative charges from 16-by-16 hexagonal silicon or CZT detector arrays, at a pitch size of 250 μm, to achieve good spatial resolution and the ability to record the energy of a detected photon as well as its position. The readout is done by bumpbonding the anodes to the inputs of the ASIC. Each channel of the ASIC provides low-noise charge amplification, high-order shaping with baseline stabilization, discrimination, extraction of amplitude (with neighbour channels), multiplexing, and dissipates ~0.6 mW. A smart readout of the triggered pixel and its adjacent six pixels in the hexagonal configuration allows reconstruction of events with charge sharing correction, and can be used to estimate the depth of the photon interaction and to suppress background events. The target equivalent noise charge (ENC) is ~10 electrons for silicon detector pixel and ~15 electrons for CZT detector pixel.
08:45-09:00 An Advanced CuCu Hybrid Bonding For Novel Stacked CMOS Image Sensor R01 Y. Kagawa 1 , N. Fujii 2 , K. Aoyagi 2 , Y. Kobayashi 1 , S. Nishi 1 , S. Takeshita 1 , J. Taura 1 , H. Takahashi 2 , Y. Nishimura 2 , K. Tatani 2 , M. Kawamura 1 , H. Nakayama 1 , T. Nagano 2 , K. Ohno 2 , H. Iwamoto 2 , S. Kadomura 1 , T. Hirayama 2 . 1 Sony Semiconductor Manufacturing, Japan; 2 Sony Semiconductor Solutions, Japan
X-ray free-electron lasers (XFELs) provide very intense X-ray pulses suitable for macromolecular crystallography. Each X-ray pulse typically lasts for tens of femtoseconds and the interval between pulses is many orders of magnitude longer. Here we describe two novel acoustic injection systems that use focused sound waves to eject picoliter to nanoliter crystal-containing droplets out of microplates and into the X-ray pulse from which diffraction data are collected. The on-demand droplet delivery is synchronized to the XFEL pulse scheme, resulting in X-ray pulses intersecting up to 88% of the droplets. We tested several types of samples in a range of crystallization conditions, wherein the overall crystal hit ratio (e.g., fraction of images with observable diffraction patterns) is a function of the microcrystal slurry concentration. We report crystal structures from lysozyme, thermolysin, and stachydrine demethylase (Stc2). Additional samples were screened to demonstrate that these methods can be applied to rare samples.
To take full advantage of advanced data collection techniques and high beam flux at next-generation macromolecular crystallography beamlines, rapid and reliable methods will be needed to mount and align many samples per second. One approach is to use an acoustic ejector to eject crystal-containing droplets onto a solid X-ray transparent surface, which can then be positioned and rotated for data collection. Proof-of-concept experiments were conducted at the National Synchrotron Light Source on thermolysin crystals acoustically ejected onto a polyimide `conveyor belt'. Small wedges of data were collected on each crystal, and a complete dataset was assembled from a well diffracting subset of these crystals. Future developments and implementation will focus on achieving ejection and translation of single droplets at a rate of over one hundred per second.
X-ray Active Matrix Pixel Sensors (XAMPS) were designed and fabricated as part of a detection system for the X-ray Pump Probe (XPP) instrument at the Linac Coherent Light Source (LCLS). XAMPS based on J-FET technology were produced on 100 mm high-resistivity silicon, typically 400 μm-thick. The prototypes are square matrices with n rows and n columns with n=16, 32, 64, 128, 256, 512. Each pixel of the matrix is 90 × 90 μm 2 and contains a JFET switch to control the charge readout. The small features of the design presented some technological challenges fully addressed during this production. The first prototypes were tested at the National Synchrotron Light Source (NSLS) with a monochromatic beam of 8 keV and millisecond readout and exhibit good performances at room temperature.