Infineon Technologies Ag

Fresenius Medical Care Deutschland Gmbh

Fresenius Medical Care Ag & Co Kgaa

Jenspeter Rau

Siegfried Schwarzl

Gerhard Wiesen

Frank-Michael Kamm

Stefan Wurm

Thomas Pohl

Silvio Teuber

A focused light beam is directed onto a surface patch of a mask and decomposed into partial beams by diffraction at a structure formed on the surface of the mask. Detectors are set such that the intensity of at least two orders of diffraction can be measured. The measured intensities are compared with one another. By way of example, a quotient can be ascertained. The operations are repeated for adjacent surface patches. If the absolute values of the measured intensities fluctuate with a constant quotient, then a variation of the reflection or transmission over the surface of the mask is inferred. If the quotient varies as well, then line width fluctuations within the structure on the mask are inferred.

Method and apparatus for determining local variation of the reflection or transmission behavior over a mask surface

An apparatus for measuring an exposure intensity on a wafer is disclosed. According to one aspect, an apparatus for measuring an exposure intensity on a wafer includes an exposure device for generating a radiation having a predetermined wavelength. Further, the apparatus includes a mask at a first predetermined distance from the exposure device for patterned exposure of a wafer A detection device detects the exposure intensity at a second predetermined distance from the exposure device. A compensation device can be moved into the beam path between the exposure device and the detection device for the purpose of influencing the beam path.

Apparatus for measuring an exposure intensity on a wafer

An opening is formed in a light-absorbing layer on a mask by applying a second resist above a first resist on the layer. A first exposure step with subsequent development of the second resist leads to the formation of a first opening in the developed second resist. The first resist is uncovered on an area within the opening. A second exposure step is performed by irradiation of the mask in a second segment, which is laterally offset with respect to the first opening, so that an incomplete portion of the area of the uncovered first resist is exposed within the opening. After a further development step and an etching step with formation of a second opening in the developed first resist with a transfer of the portion into the light-absorbing layer, this opening has a diameter smaller than both the first and the second segment.

Method for forming an opening in a light-absorbing layer on a mask

A reflection mask, preferably, an EUV reflection mask, for imaging a pattern that has or is formed on the mask onto a semiconductor wafer with extreme ultraviolet radiation or soft X-radiation includes a substrate, a reflection layer thereon reflecting incident radiation, an absorption layer thereon absorbing incident radiation, and a hard mask thereon of a material having an etching selectivity with respect to absorbent material of the absorption layer. After exposure and development of the resist, the pattern is transferred into the hard mask in a first etching step and the resist is removed, and inspection of the pattern in the hard mask detects defects in the hard mask. Defects can be repaired by FIB. Gallium ions are implanted in the absorption layer instead of in the reflection layer, rendering a buffer layer obsolete and allowing lower aspect ratios of trenches on the finished reflection mask.

Reflection mask and method for fabricating the reflection mask

A reflective optical mirror for semiconductor fabrication includes a capping layer above a reflective multilayer sequence. A doping is provided for the capping layer and an artificial oxide layer is grown on the capping layer with the aid of hydrogen peroxide, in particular in the presence of a catalyst. The artificially grown oxide layer is more homogeneous than a naturally grown oxide and thereby improves optical properties of the mirror during a lithographic exposure of semiconductor products.

Reflective mirror for lithographic exposure and production method

A radiation-sensitive coating material, in addition to a base polymer, has a solvent and a radiation-active substance which forms an acid on irradiation by light (including energetic electrons or ions), a fluorescent substance which alters its fluorescence property subject to a change in the acid content of its surroundings. In a process for exposing a substrate coated with the coating material at least one sensor in the exposure chamber of the exposure apparatus measures the intensity of the change in fluorescence spectrum as a function of time during the exposure operation. From the course of intensity at the time of an individual line of the fluorescence spectrum or the intensity integrated over a wavelength interval it is possible to determine the endpoint of the exposure operation by way of electronic algorithms. Deviations from experimentally determined ideal curves of the intensity course provide information on erroneous functions in the course of coating material application and exposure.

Photosensitive coating material for a substrate and process for exposing the coated substrate

In an EUV reflection mask which is set up for region-by-region exposure of a radiation-sensitive layer lying on a semiconductor wafer by means of radiation in the spectral region of extreme ultraviolet radiation, which radiation is reflected at the mask, patterns are written directly into a multilayer layer, lying on a substrate, by means of a focused laser beam or by ion implantation, the reflectivity of which patterns is reduced by more than 90% compared with the reflectivity of the regions that are not written to, and which patterns form the radiation-absorbing regions of the mask. This avoids the shadowing of the exposure radiation that is incident at a small angle, said shadowing occurring with the use of the EUV reflection masks that have been customary heretofore.

Growing community of inventors

Munich, Germany

Jenspeter Rau