LASER-PLASMA X-RAY CONTACT MICROSCOPY OF LIVING SPECIMENS USING A CHEMICALLY AMPLIFIED EPOXY RESIST

We report on the use of an epoxy based chemically amplified resist, to produce x-ray images of living biological specimens, exposed with las er plasma generated soft x rays, in the water window (2.3-4.4 nm). The photoresist response was at least two orders of magnitude ''faster'' than polymethyl methacrylate, the standard resist used so far in soft x-ray contact microscopy. Atomic force and scanning electron microscop y of the biological specimen images, recorded in the resist, clearly s howed the flagella of the motile green alga, chlamydomonas, suggesting a lateral resolution better than 150 nm. The resist was also capable of providing height features, as small as 20 nm, in atomic force micro scope depth profiles and discriminating the flagella intersection area s. (C) 1998 American Institute of Physics. [S0003-6951(98)00225-3].