摘要 |
Imaging errors in optical exposure units for the lithographic structuring of semiconductors are determined. First, a latent image of a mask is first produced in a photoactivatable layer by exposure using the optical exposure unit to be tested. After heat treating for increasing the contrast and developing the exposed resist, the latter is treated with an amplification agent which preferably diffuses into the exposed parts of the photoresist. There, it reacts with groups of the photoresist. This leads to an increase in the layer thickness of the resist in the exposed parts. A topographical image of the surface of the photoresist, which can be created, for example, by scanning electron microscopy, then indicates imaging errors by protuberances which are located outside the image of the mask. The method permits testing of optical exposure units under production conditions and thus facilitates the adjustment and the checking of all components of the exposure system used for the production of microchips.
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