Deguzman, Lou | Search NASA

NASA NTRS2021

Ni-Silicide Schottky Barrier Micropyramidal Photodetector Array

In attempt to increase the quantum yield of metal/silicide Schottky barrier photodetectors, in this work we fabricated and tested Si micropyramidal arrays which are capable to resonantly trap photons in the photodetector areas. To simplify testing, Ni/silicide Schottky barrier photodetectors were formed on the entire 1.5  1.5 mm areas occupied by the micropyramidal arrays. Preliminary testing results revealed potentially stronger photoresponse of micropiramids with narrow tops, but further studies are required to compare the performance of such novel photodetector arrays with different geometrical parameters of micropyramids.

Astratov, Vasily N.↗

NASA NTRS2021

Anisotropic Wet Etching of Si as a Fabrication Tool Enabling 3-D Microphotonics Structures and Devices

It is shown that due to high speed and large volume of production, anisotropic wet etching of Si is a unique method of manufacturing high quality micropyramidal arrays for silicon photonics. Four types of arrays were fabricated: (i) square pyramids with the 54.7 slope of the sidewall surface, (ii) microcones with the 45 slope of sidewall surface, (iii) inverted square pyramids with 54.7 slope, and (iv) inverted triangular pyramids with different angles of the sidewalls. It is shown that the first type of arrays has a capability to produce tightly focused mid-wave infrared (MWIR) beams at the tips of the pyramids. Other arrays can be also used as light concentrators and various multifunctional microphotonic components.

Astratov, Vasily N.↗