Process for the wet-chemical treatment of one side of silicon wafers

1. A process for wet-chemical treatment of one side of a silicon wafer using a liquid bath, during which treatment the silicon wafer lays on conveyor means and the entire surface of the underside to be treated is conveyed through or over liquid located in the liquid bath, wherein the conveyor means are positioned within the liquid bath, further wherein the top side which is not to be treated is always positioned above the liquid, further wherein a meniscus is positioned at edges of the wafer.

2. The process as claimed in claim 1 , characterized in that the silicon wafer is processed continuously in a once-through process.

3. The process as claimed in claim 2 , characterized in that the underside of the silicon wafer is lowered into the liquid bath.

4. The process as claimed in claim 1 , characterized in that as part of a production line the silicon wafer is conveyed horizontally through the treatment liquid located in the liquid bath.

5. The process as claimed in claim 4 , characterized in that the liquid bath used is a tank whose peripheral edge is lower than the level of the treatment liquid.

6. The process as claimed in claim 1 , characterized in that the edges of the silicon wafer are also treated.

7. The process as claimed in claim 1 , characterized in that the treatment is an etching step and is carried out in a liquid composition which contains NaOH, KOH, HF, HNO 3 , HF with O 3 , and/or HF with oxidizing agent.

8. The process as claimed in claim 7 , characterized in that the oxidizing agent is an oxidizing acid.

9. The process as claimed in claim 8 , characterized in that the liquid composition contains at least one additive for binding the gases formed during the etching.

10. The process as claimed in claim 7 , characterized in that the liquid composition contains at least one additive for binding the gases formed during the etching.

11. The process as claimed in claim 1 , characterized in that the conveyor means are provided in the form of belts or conveyor rolls.

12. The process as claimed in claim 1 , characterized in that the treatment is an etching, coating or cleaning step.

13. The process as claimed in claim 1 , characterized in that the top side of the wafer is not protected during treatment.

14. A process for wet-chemical treatment of one side of a silicon wafer using a liquid bath, during which treatment the wafer lays on conveyor means and is conveyed with the underside to be treated through or over liquid located in the liquid bath, wherein the level of the liquid being contacted by the underside is maintained above the level of the bath surface not being contacted by the underside as a result a meniscus forms between the underside and a surface of the liquid in the liquid bath, further wherein the top side which is not to be treated is always positioned above the level of the liquid.

15. The process as claimed in claim 14 , characterized in that the underside of the silicon wafer is lowered into the liquid bath over the production line.

16. The process as claimed in claim 14 , characterized in that the silicon wafer is conveyed horizontally through the treatment liquid located in the liquid bath over a production line.

17. The process as claimed in claim 16 , characterized in that the liquid bath used is a tank whose peripheral edge is lower than the level of treatment liquid.

18. The process as claimed in claim 14 , characterized in that the conveyor means are provided in the form of belts or conveyor rolls.

19. The process as claimed in claim 18 , characterized in that the conveyor rolls are in each case arranged on axle elements.

20. The process as claimed in claim 19 , characterized in that each axle element is encapsulated in a fluid-tight manner with respect to the treatment liquid.

21. The process as claimed in claim 14 , characterized in that the edges of the silicon wafer are also treated.

22. The process as claimed in claim 14 , characterized in that the silicon wafer is processed continuously in a once-through process.

23. The process as claimed in claim 10 , characterized in that the treatment is an etching, coating or cleaning step.

24. The process as claimed in claim 23 , characterized in that the etching liquid is carried out in a liquid composition which contains NaOH, KOH, HF, HNO 3 , HF with O 3 , and/or HF with oxidizing agent.

25. The process as claimed in claim 24 , characterized in that the oxidizing agent is an oxidizing acid.

26. The process as claimed in claim 14 , characterized in that the top side of the wafer is not protected during treatment.

27. A process for wet-chemical treatment of electrically conductive edges of a silicon wafer using a liquid bath, during which treatment the silicon wafer lays on conveyor means, wherein the underside and electrically conductive edges to be treated are conveyed through or over etching liquid located in the liquid bath to remove conductivity from the edges, further wherein the conveyor means are positioned within the liquid bath, further wherein an electrically conductive top side which is not to be treated is always positioned above the liquid, further wherein a meniscus is positioned at edges of the wafer.