Process and apparatus for the production of a metal oxide layer

Process for producing a metal oxide layer on a substrate, the metal oxide layer being free of cracks, the process comprising:

• holding the substrate in an evacuated vacuum chamber, evacuated to 10.sup.-1 mbar or lower;
• setting particles of a metal free into the chamber, the freed metal particle having a kinetic energy;
• introducing oxygen into the chamber;
• keeping a temperature of the substrate below 900.degree. C.;
• reacting said particles with said oxygen to form metal oxide deposition on said substrate;
• steadily raising a ratio of a quantity of the oxygen introduced per unit time into said chamber to the metal particles freed into said chamber per unit time, controlled for each mono-atomic or mono-molecular layer deposited on the substrate, to result in a steadily rising degree of oxidation of metal oxide on said substrate;
• and
• limiting the kinetic energy of the metal particles freed into said chamber to a maximum of 10 eV at said substrate.