Etching apparatus
First Claim
Patent Images
1. A method of etching a semiconductor device, the method comprising:
- filling an etchant tank with a liquid etching solution;
after filling the etchant tank, submerging a surface of a substrate in the liquid etching solution;
removing a sample from the liquid etching solution;
analyzing the sample to determine a concentration of an oxidant within the sample;
introducing a makeup amount of the oxidant into the liquid etching solution based upon the concentration of the oxidant from analyzing the sample; and
etching a semiconductor substrate with the liquid etching solution to form an etched surface, wherein after the etching the semiconductor substrate the etched surface is free from hillocks.
0 Assignments
0 Petitions
Accused Products
Abstract
A system and method of etching a semiconductor device are provided. Etching solution is sampled and analyzed by a monitoring unit to determine a concentration of components within the etching solution, such as an oxidant concentration. Then, based upon such measurement, a makeup amount of the components may be added be a makeup unit to the etching solution to control the concentration of the components within the etching system.
62 Citations
20 Claims
-
1. A method of etching a semiconductor device, the method comprising:
-
filling an etchant tank with a liquid etching solution; after filling the etchant tank, submerging a surface of a substrate in the liquid etching solution; removing a sample from the liquid etching solution; analyzing the sample to determine a concentration of an oxidant within the sample; introducing a makeup amount of the oxidant into the liquid etching solution based upon the concentration of the oxidant from analyzing the sample; and etching a semiconductor substrate with the liquid etching solution to form an etched surface, wherein after the etching the semiconductor substrate the etched surface is free from hillocks. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A method of manufacturing a semiconductor device, the method comprising:
-
receiving a substrate into an etchant tank holding an etchant, the etchant comprising a strong base, a surfactant, and an oxidant; removing a sample of the etchant from the etchant tank and sending the sample to a monitoring unit, the monitoring unit comprising an oxidant analysis unit; analyzing the sample of the etchant; determining an amount of makeup to add to the etchant in the etchant tank; mixing in a makeup unit one or more of a makeup strong base, a makeup surfactant, and a makeup oxidant to form the amount of makeup, the makeup unit coupled to a first output from a strong base unit, a second output from a surfactant unit, and a third output from an oxidant unit; and adding the amount of makeup to the etchant. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14)
-
-
15. A method of manufacturing a semiconductor device, the method comprising:
-
applying an etchant to a surface of a substrate, the surface being submerged in the etchant, the substrate and the etchant being located in an etching tank, the etchant comprising; a strong base to etch the substrate; a surfactant to modify a selectivity of the etchant to a first crystallographic orientation; and an oxidant to react with the substrate to repel chemical reaction by-products from a surface of the substrate and impede hillock regrowth; analyzing a first concentration of the strong base; analyzing a second concentration of the surfactant separately from the analyzing the first concentration of the strong base; analyzing a third concentration of the oxidant separately from the analyzing the first concentration of the strong base and separately from the analyzing the second concentration of the surfactant; determining an amount to add of each of the strong base, the surfactant, and the oxidant; mixing a first makeup amount of the strong base, a second makeup amount of the surfactant, and a third makeup amount of the oxidant to form a makeup stream; and titrating the makeup stream into the etchant. - View Dependent Claims (16, 17, 18, 19, 20)
-
Specification