A new method for manufacturing a stamp or a mold, which differs from well-known LIGA technology, is described. They can be used to mold biochips of various plastics. A typical sequence of operations in LIGA technology is as follows: the formation of a thick resistive mask by deep X-ray lithography, the creation of a stamp (or mold) by galvanoplasty and the fabrication of plastic products using a stamp (or mold). This report describes a different sequence of operations: the formation of a thick resistive mask by deep photolithography on the working surface of the blank of a stamp (or a mold), the creation of a stamp relief by plasma chemical etching through a resistive mask, and the stamping (or molding) of plastic products, using the resulting stamp (or mold). A new method for the polymerization of plexiglass from electron-irradiated methyl methacrylate (MMA) prepolymer is also described. It has advantages over polymerization methods using benzoyl peroxide as the initiator of polymerization, because it expands the spectral range of transparency of the resulting plexiglass. This makes it possible to combine biochips produced by this technology with laser-induced fluorescence to detect analyzed samples in a wider spectral range.