Focusing of x-rays using micromachined silicon lobster eye lenses

Conference · Wed Jan 01 04:00:00 EST 1992 · American Astronomical Society, Bulletin; (United States)

OSTI ID:6669969

Chen, A; Kaaret, P; Kenny, T

We are developing a novel x-ray lens, based on a one-dimensional analogue of the optical system of the lobester's eye, that is capable of making spatially resolved observations of celestial x-ray sources up to 10 keV with an angular resolution of 30[double prime] and an essentially unlimited field of view. Most standard x-ray telescopes use large reflecting surfaces curved in a unique shape to ofcus x-rays by total external reflection. The lobester eye lens consists of a large number of small, closely-packed reflecting surfaces that are flat and parallel. Lobester eye designs to date have consisted of large arrays of macroscopically aligned reflecting planes. These lenses have had the disadvantage of large pore width, leading to poor angular resolution, and large size and weight. The need for smaller, more closely spaced, flat, parallel surfaces lends itself to silicon micromachining. We have fabricated and tested silicon lenses suitable for focusing soft x-rays. We used a concentrated KOH solution to anisotropically etch (110) oriented single crystal silicon wafers; the resulting surfaces were aligned with the (111) planes perpendicular to the face. The pores were 50 [mu]m wide and 800 [mu]m deep, for an aspect ratio fo 40:1. We report on the fabrication techniques, measurements of the surface microroughness of the reflecting planes, and x-ray beam tests of the lenses. Future development will focus on coating the reflecting surfaces with metal to increase the reflection efficiency and on curing the lenses to image objects at astronomical distances. X-ray lenses may also be applied to other types of research.

• OSTI ID: 6669969
• Report Number(s): CONF-930189--
• Conference Information: Journal Name: American Astronomical Society, Bulletin; (United States) Journal Volume: 24:4
• Country of Publication: United States
• Language: English

Related Subjects

440100* -- Radiation Instrumentation
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ASPECT RATIO
COSMIC RAY SOURCES
COSMIC X-RAY SOURCES
ELECTROMAGNETIC RADIATION
ELEMENTS
FABRICATION
FOCUSING
IONIZING RADIATIONS
LENSES
MEASURING INSTRUMENTS
RADIATIONS
RESOLUTION
SEMIMETALS
SILICON
SOFT X RADIATION
TESTING
X RADIATION