Lithography device which uses a source of radiation in the extreme ultraviolet range and multi-layered mirrors with a broad spectral band in this range

A lithography device comprising:

• a support (16) for a sample intended to be exposed in accordance with a specified pattern,
• a mask (24) comprising the specified pattern in an enlarged form,
• a source (22) of radiation in the extreme ultraviolet range,
• optical means (26) for collection and for transmission of the radiation to the mask, the latter supplying an image of the pattern in enlarged form, and
• optical means (29) for reduction of this image and for the projection of the reduced image onto the sample,
• the mask, the optical means for the collection and the transmission and the optical means for reduction and projection comprising multi-layered mirrors, each multi-layered mirror comprising a substrate (74) and, on this substrate, a stack of layers (76) of a first material and of layers (78) of a second material which alternate with the layers of the first material, this first material having an atomic number greater than that of the second material, the first and second layers co-operating to reflect the extreme ultraviolet radiation, the stack having a free surface (80) onto which the radiation to be reflected arrives,
• this device being characterized in that the source comprises at least one solid target (28), having first and second faces, this target being capable of emitting the extreme ultraviolet radiation by interAction with a laser bean (34) focused on the first face (30) of the target, this target being capable of emitting, in an anisotropic way, a part (36) of the extreme ultraviolet radiation from the second face (37) of this target, in that the optical means (26) for collection and for transmission are provided in order to transmit, to the mask (24), the part (36) of the extreme ultraviolet radiation coming from the second face (37) of the target of the source and in that the thickness of pairs of adjacent layers (76, 78), in the stack of layers that each mirror comprises, is a monotonic function of the depth in the stack, this depth being counted from the free surface (80) of the stack.