Method for coating substrates and mask holder

When coating substrates it is frequently desired that the layer thickness should be a certain function of the position on the substrate to be coated. To control the layer thickness a mask is conventionally arranged between the coating particle source and the substrate. This leads to undesirable shadow effects. In addition, is has so far only been possible to obtain rotationally symmetrical thickness distributions. It is now proposed that masks should be used having apertures aligned according to a regular grid on the mask surface. Such a mask with a mask holder comprising a base frame (2), an intermediate frame (3) and a mask frame (4) which are joined one to the other by means of double hinges (5a, a', b, b'), is moved arbitrarily in the mask plane. By this means arbitrary thickness distributions can be achieved when coating substrates at reasonable cost.