Method for manufacturing semiconductor device
View Patent ↗An object of the present invention is to provide a method for manufacturing a semiconductor device in which, after crystallizing by using an element that promotes crystallization, holes are prevented from being generated in a crystalline semiconductor film with a concentration of the element in the crystalline semiconductor film decreased by performing gettering. To solve the problem, as a feature of the structure of the invention, in the case of removing a silicon oxide film formed over the semiconductor film, an etchant made of a solution containing fluorine and a substance having surface activity is used.
1. A method for manufacturing a semiconductor device comprising the steps of:
forming a first silicon oxide film over a first crystalline semiconductor film crystallized by using an element that promotes crystallization, the first crystalline semiconductor film comprising silicon;
forming a second semiconductor film comprising amorphous silicon over the first silicon oxide film;
performing a heat treatment wherein a second silicon oxide film is formed on the second semiconductor film; and
removing the second silicon oxide film by using a solution containing fluorine and a substance having surface activity.
2. A method for manufacturing a semiconductor device comprising the steps of:
irradiating a first crystalline semiconductor film crystallized by using an element that promotes crystallization with laser light, the first crystalline semiconductor film comprising silicon;
removing a first silicon oxide film formed on the surface of the first crystalline semiconductor film with the irradiation of the laser light by using a solution containing fluorine and a substance showing having surface activity;
forming a second silicon oxide film over the first crystalline semiconductor film;
forming a second semiconductor film comprising amorphous silicon over the second silicon oxide film;
performing a heat treatment wherein a third silicon oxide film is formed on the second semiconductor film; and
removing the third silicon oxide film by using a solution containing fluorine and a substance having surface activity.
3. A method for manufacturing a semiconductor device comprising the steps of:
forming a first silicon oxide film over a first crystalline semiconductor film crystallized by using an element that promotes crystallization, the first crystalline semiconductor film comprising silicon;
forming a second semiconductor film comprising amorphous silicon over the first silicon oxide film;
performing a heat treatment wherein a second silicon oxide film is formed on the second semiconductor film; and
removing the second silicon oxide film by using a solution containing fluorine and a substance having surface activity;
removing the second semiconductor film; and
removing the first silicon oxide film formed over the first crystalline semiconductor film by using a solution containing fluorine and a substance having surface activity.
4. A method for manufacturing a semiconductor device comprising the steps of:
irradiating a first crystalline semiconductor film crystallized by using an element that promotes crystallization with laser light, the first crystalline semiconductor film comprising silicon;
removing a first silicon oxide film formed on the surface of the first crystalline semiconductor film with the irradiation of the laser light by using a solution containing fluorine and a substance having surface activity;
forming a second silicon oxide film over the first crystalline semiconductor film;
forming a second semiconductor film comprising amorphous silicon over the second silicon oxide film;
performing a heat treatment wherein a third silicon oxide film is formed on the second semiconductor film; and
removing the third silicon oxide film by using a solution containing fluorine and a substance having surface activity;
removing the second semiconductor film; and removing the second silicon oxide film formed over the first crystalline semiconductor film by using a solution containing fluorine and a substance having surface activity.
5. The method for manufacturing a semiconductor device according to claim 1 , wherein the substance having surface activity is one or more kinds of organic solvent, organic acid, and a surface active agent.
6. The method for manufacturing a semiconductor device according to claim 2 , wherein the substance having surface activity is one or more kinds of organic solvent, organic acid, and a surface active agent.
7. The method for manufacturing a semiconductor device according to claim 3 , wherein the substance having surface activity is one or more kinds of organic solvent, organic acid, and a surface active agent.
8. The method for manufacturing a semiconductor device according to claim 4 , wherein the substance having surface activity is one or more kinds of organic solvent, organic acid, and a surface active agent.
9. The method for manufacturing a semiconductor device according to claim 1 , wherein the solution containing fluorine is a solution at least containing hydrofluoric acid.
10. The method for manufacturing a semiconductor device according to claim 2 , wherein the solution containing fluorine is a solution at least containing hydrofluoric acid.
11. The method for manufacturing a semiconductor device according to claim 3 , wherein the solution containing fluorine is a solution at least containing hydrofluoric acid.
12. The method for manufacturing a semiconductor device according to claim 4 , wherein the solution containing fluorine is a solution at least containing hydrofluoric acid.
13. The method for manufacturing a semiconductor device according to claim 1 , wherein the solution containing fluorine is a solution at least containing hydrofluoric acid and ammonium fluoride.
14. The method for manufacturing a semiconductor device according to claim 2 , wherein the solution containing fluorine is a solution at least containing hydrofluoric acid and ammonium fluoride.
15. The method for manufacturing a semiconductor device according to claim 3 , wherein the solution containing fluorine is a solution at least containing hydrofluoric acid and ammonium fluoride.
16. The method for manufacturing a semiconductor device according to claim 4 , wherein the solution containing fluorine is a solution at least containing hydrofluoric acid and ammonium fluoride.
17. The method for manufacturing a semiconductor device according to claim 1 , wherein the pH of the solution containing fluorine and surface active agent is 5 or more.
18. The method for manufacturing a semiconductor device according to claim 2 , wherein the pH of the solution containing fluorine and surface active agent is 5 or more.
19. The method for manufacturing a semiconductor device according to claim 3 , wherein the pH of solution containing fluorine and surface active agent is 5 or more.
20. The method for manufacturing a semiconductor device according to claim 4 , wherein the pH of the solution containing fluorine and surface active agent is 5 or more.
21. The method for manufacturing a semiconductor device according to claim 1 , wherein the pH of the solution containing fluorine and surface active agent is 5.5 or more.
22. The method for manufacturing a semiconductor device according to claim 2 , wherein the pH of the solution containing fluorine and surface active agent is 5.5 or more.
23. The method for manufacturing a semiconductor device according to claim 3 , wherein the pH of the solution containing fluorine and surface active agent is 5.5 or more.
24. The method for manufacturing a semiconductor device according to claim 4 , wherein the pH of the solution containing fluorine and surface active agent is 5.5 or more.
25. The method for manufacturing a semiconductor device according to claim 1 , wherein the semiconductor device is incorporated into an electronic device selected from the group consisting of a display device, a camera, a computer, a portable information terminal, and a game apparatus.
26. The method for manufacturing a semiconductor device according to claim 2 , wherein the semiconductor device is incorporated into an electronic device selected from the group consisting of a display device, a camera, a computer, a portable information terminal, and a game apparatus.
27. The method of manufacturing a semiconductor device according to claim 3 , wherein the semiconductor device is incorporated into an electronic device selected from the group consisting of a display device, a camera, a computer, a portable information terminal, and a game apparatus.
28. The method for manufacturing a semiconductor device according to claim 4 , wherein the semiconductor device is incorporated into an electronic device selected from the group consisting of a display device, a camera, a computer, a portable information terminal, and a game apparatus.