| 摘要 |
The invention relates to a device and a method for depositing semiconductor layers, in particular made of a plurality of components on one or more substrates (21) contacting a susceptor (2), wherein process gases can be introduced into the process chamber (1) through flow channels (15, 16; 18) of a gas inlet organ (8), together with a carrier gas, said carrier gas permeating the process chamber (1) substantially parallel to the susceptor and exits through a gas outlet organ (7), wherein the products of decomposition build up the process gases as a coating at least in regions on the substrate surface and on the surface of the gas outlet organ (7) disposed downstream of the susceptor (2) at a distance (D) from the downstream edge (21) thereof. In order to deposit contamination-free layers in sequential process steps without intermediate replacement or intermediate cleaning of the gas outlet organ, according to the invention the distance (D) is great enough to prevent products of decomposition outgassing from the coating of the gas outlet organ (7) at the second process temperature from reaching the substrate (21) by counterflow diffusion. |
| 主权项 |
1. A method for depositing semiconductor layers consisting of a plurality of components on one or more substrates (21) which are supported on a susceptor (2), the susceptor forming a wall portion of a process chamber (1), said wall portion being heated by a heating device (5) to a process temperature, process gases containing an organometallic component of the II or III main group and a hydride of the V or VI main group and provided by a gas mixing system (22) being introduced together with a carrier gas into the process chamber (1) through flow channels (15, 16, 18) of a gas inlet element (8), which carrier gas flows through the process chamber (1) substantially parallel to the susceptor and leaves through a gas outlet element (7), the process gases decomposing into products of decomposition in a pyrolytic manner at least on a surface of the heated substrate (21) and the decomposition products growing to form a coating at least in certain regions on the substrate surface and on a surface of the gas outlet element (7) that is located downstream at a spacing (D) from a downstream edge (2′) of the susceptor, a first process step being carried out at a first process temperature and after that, a second process step being carried out at a second process temperature without intervening cleaning or exchange of the gas outlet element (7) coated by growth of decomposition products, the second process temperature being higher than the first process temperature by at least 500° C.,
the method characterized in that the spacing (D) is sufficiently great to prevent the decomposition products, or fragments or agglomerations of the decomposition products, evaporating, at the second process temperature, from the coating on the gas outlet element (7), from reaching the substrate (21) by reverse flow diffusion or recirculation, and further characterized in that heating of the gas outlet element (7) is controlled during the two process steps so that its surface temperatures during both process steps differ from one another only by 100° C. at a maximum. |
