Low-Energy Charged-Particle Detection via an Avalanche Silicon Detector coupled to an Amorphous Silicon Active Layer

This SBIR Phase I project will develop a solid-state sensor with on-chip amplification to deliver low-energy (< 10 keV/e-) particle-detection with similar sensitivity and timing performance as existing vacuum-tube multiplication instruments, but do so at low-bias, low-cost, and in a compact, ruggedized package. The work will complete the prototype development of a silicon-based detector scheme for electrons, protons, and heavy ions with a thin-film (4 – 1000 nm) amorphous silicon front active layer and an integrated silicon avalanche layer for on-chip amplification. The amorphous silicon creates charge-pairs for even the lowest of energies, and the p+/n silicon detector produces multiplication gain at low voltage (< 100 V). Compared with channel electron multipliers or microchannel plates that operate at ~1 kV, this not only reduces the power requirements, but it eliminates the arcing risks that can accompany compact instrument and spacecraft designs. The detector: (a) eliminates the need for the ultra-high vacuum required for the vacuum tube technologies, (b) tolerates dust via its solid-state design, and (c) can deliver charged-particle flux measurements with CMOS integration. The Phase I work will establish the simplest design that allows low-energy particle detection by evaluating: (a) thinned silicon avalanche diodes operating at ~50 V, (b) amorphous silicon thin-film diodes operating at 0 V, and (c) a combined device that marries the amorphous silicon sensing layer with the multiplying silicon back layer.

The technology developed under this SBIR will help advance solar science and mitigate the effects of harmful amounts of space radiation, whether it consists of high energy charged particles or secondary protons following solar particle events. The underlying detection technology can possess similar sensitivity to existing vacuum-tube technologies, but it will deliver the sensing capability at low bias and power in a rugged, compact, low-cost package, which can enable ubiquitous sensors for solar weather monitoring, planetary exosphere studies, and heliospheric characterization. By allowing one to better correlate the solar particle emissions with the driving feature near the photosphere, the technology can help to identify the origins and causes of the solar wind, solar energetic particles, and the Sun’s magnetic field. Thus, future NASA heliophysics missions will gain far greater specificity in mapping the spectral, directional, and composition of solar-driven particles. Beyond heliophysics, the solid-state sensor can be used to precisely characterize atmospheric and soil samples captured and ionized during planetary studies. In fact, the general amplification technology can be applied to photonic detection as well, yielding another pathway through which high resolution x-ray and gamma-ray imaging can be elicited. We envision initial technological infusion to be with the Artemis program as a solar weather monitoring tool for Lunar studies. detection, but it can find use in the fabrication of silicon-based ultraviolet APDs. These can find wide applicability, useful for biological imaging applications in both defense and commercial settings, flame monitoring, ladar navigation, and in an enhanced night-vision concept. For instance, if a UV flash illuminator and 2-D pixel array are coupled to form a 3-D imaging ladar, then one can form single-photon images at successive ranges by synchronously range-gating the APD array with the illumination pulse. Multiple single-photon image frames can be collected at each range over a period of time in order to form grey-scale intensity images of the scene. If applied to neutron or gamma-ray detection, on-chip amplification provides an alternative pathway through which the signal-to-noise ratio can be enhanced, complementing the large body of research conducted in reducing the noise via cooling methods or alternative materials searches. For the specific sensing of primary or secondary charged particles and high-energy photons, the successful development of a low cost, high performance design will impact the entire industry, standing as a viable alternative to exotic materials. Thus, optical cameras, medical imaging instruments, and military radiation instruments would all be impacted by the successful development of an amplifying particle sensor.

This is a mature technology (TRL 7+) — the realistic path in is usually NASA's Technology Transfer Program: licensing an existing NASA patent, or a Space Act Agreement to use NASA facilities/expertise directly. NASA also runs a startup licensing program with no upfront fee for companies formed to commercialize a specific NASA technology.

None of these are guaranteed paths for this specific project — TechPort itself doesn't have an "apply" button. Reaching out to the contact(s) above with a specific question is usually the fastest way to find out what's actually open.