CLEANING MEANS FOR LARGE AREA PECVD DEVICES USING A REMOTE PLASMA SOURCE
This invention describes a method for cleaning a deposition chamber that is compatible with large area deposition. It comprises transport of activated gas from a remote plasma source to an area in the chamber in a uniform way through at least two injection points on equivalent paths for the reactive species. A respective gas injection system for the distribution of activated reactive gas comprises a source of reactive gas, a tubing for distributing the gas and an evacuable chamber. The gas is discharged to the tubing having at least one inlet constructively connected to the source and at least two outlets open to the chamber, thereby forming at least partially independent tube branches, wherein the length and the cross-section perpendicular to the gas flow of each tube branch, calculated between inlet and each respective outlet is essentially equal.
1 . A method for cleaning a vacuum deposition construed for substrates of 1 meter square or more, the method comprising: transport of activated gas from a remote plasma source into the chamber in a uniform way through at least two injection points, wherein the path for the activated gas is equivalent.
2 . Method according to claim 1 wherein said equivalent paths are equivalent in terms of material, temperature, length, diameter, pipe configuration or pressure drop.
3 . Method according to claim 1 wherein said remote plasma source is being operatively connected to several vacuum deposition chambers for parallel cleaning action.
4 . A gas injection system for the distribution of activated reactive gas in a vacuum deposition chamber construed for substrates of 1 meter square or more comprising a source of reactive gas, a remote plasma source for activating said reactive gas, a tubing for distributing said gas, said tubing having at least one inlet constructively connected to the source and at least two outlets open to the chamber, thereby forming at least partially independent tube branches, wherein the length and the cross-section perpendicular to the gas flow of each tube branch, calculated between inlet and each respective outlet is essentially equal.
5 . Gas injection system according to claim 4 , wherein each tube branch comprises a network of piping with various diameters, each branch being symmetrical for the gas injection and having essentially the same impedance.