Transparent amorphous carbon structure in semiconductor devices

• US 7,132,201 B2
• Filed: 09/12/2003
• Issued: 11/07/2006
• Est. Priority Date: 09/12/2003
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Yin, Zhiping, Li, Weimin
• Primary Examiner(s): ROSASCO, STEPHEN D
• Application Number:
  US10/661,379
• Publication Number:
  US 20050059262A1
• Time in Patent Office: 1,152 Days
• Field of Search: 430/5, 430/311, 427/249.7, 438/636, 378/35
• US Class Current: 430/5
• CPC Class Codes: H01L 21/02115 the material being carbon, e.g. alpha-C, diamond or hydrogen doped carbon
• CPC Class Codes: H01L 21/0214 the material being a silicon oxynitride, e.g. SiON or SiON:H
• CPC Class Codes: H01L 21/022 the layer being a laminate, i.e. composed of sublayers, e.g. stacks of alternating high-k metal oxides adhesion layers or buffer layers H01L21/02304, H01L21/02362
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/0237 Materials
• CPC Class Codes: H01L 21/02439 Materials
• CPC Class Codes: H01L 21/02505 consisting of more than two layers
• CPC Class Codes: H01L 21/02527 Carbon, e.g. diamond-like carbon
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 21/0332 characterised by their composition, e.g. multilayer masks, materials
• CPC Class Codes: H01L 21/3081 characterised by their composition, e.g. multilayer masks, materials
• CPC Class Codes: H01L 21/3146 Carbon layers, e.g. diamond-like layers
• CPC Class Codes: H10B 12/033 the capacitor extending over the transistor

Abstract

A transparent amorphous carbon layer is formed. The transparent amorphous carbon layer has a low absorption coefficient such that the amorphous carbon is transparent in visible light. The transparent amorphous carbon layer may be used in semiconductor devices for different purposes. The transparent amorphous carbon layer may be included in a final structure in semiconductor devices. The transparent amorphous carbon layer may also be used as a mask in an etching process during fabrication of semiconductor devices.

Claims

1. An apparatus comprising:

a semiconductor wafer including at least one alignment mark;

a device structure formed over the semiconductor wafer; and

a masking structure formed over the device structure, the masking structure including an amorphous carbon layer, wherein the amorphous carbon layer is transparent in visible light range for allowing a reading of the alignment mark in the visible light range.

2. The apparatus of claim 1, wherein the amorphous carbon layer has an absorption coefficient between about 0.15 and about 0.001 at wavelength of 633 nanometers.

3. The apparatus of claim 1, wherein the visible light range includes electromagnetic radiation having wavelengths between 400 nanometers and 700 nanometers.

4. The apparatus of claim 1, wherein the amorphous carbon layer has a thickness greater than 4000 Angstroms.

5. The apparatus of claim 4, wherein the device structure has a thickness greater than 40000 Angstroms.

6. The apparatus of claim 1, wherein the masking structure further includes a silicon oxynitride layer formed over the amorphous carbon layer.

7. The apparatus of claim 1, wherein the masking structure further includes a photoresist layer.

8. The apparatus of claim 7, wherein the masking structure further includes an antireflective layer.

9. The apparatus of claim 7 wherein the photoresist layer includes at least one opening.

10. The apparatus of claim 9, wherein the amorphous carbon layer includes at least one opening continuous with the at least one opening of the photoresist layer.

11. The apparatus of claim 1, wherein the device structure includes a layer of a conducting material.

12. The apparatus of claim 11, wherein the device structure further includes an amorphous carbon layer, wherein the amorphous carbon layer of the device structure is transparent in visible light range.

13. The apparatus of claim 1, wherein the masking structure further comprises an antireflective layer, and wherein the antireflective layer is directly contacting the amorphous carbon layer.

14. The apparatus of claim 1, wherein the masking structure comprises a silicon oxide layer, and wherein the silicon oxide layer is directly contacting the amorphous carbon layer.

15. The apparatus of claim 14, wherein the masking structure further comprises a photoresist layer, and wherein the photoresist layer is directly contacting the silicon oxide layer.

16. The apparatus of claim 1, wherein the masking structure further comprises a hydrogenated silicon oxide layer, and wherein the hydrogenated silicon oxide layer is directly contacting the amorphous carbon layer.

17. The apparatus of claim 16, wherein the masking structure further comprises a photoresist layer, and wherein the photoresist layer is directly contacting the hydrogenated silicon oxide layer.

18. The apparatus of claim 1, wherein the masking structure further comprises a silicon oxynitride layer, and wherein the silicon oxynitride layer is directly contacting the amorphous carbon layer.

19. The apparatus of claim 18, wherein the masking structure further comprises a photoresist layer, and wherein the photoresist layer is directly contacting the silicon oxynitride layer.

20. The apparatus of claim 1, wherein the masking structure further comprises a hydrogenated silicon oxynitride layer, and wherein the hydrogenated silicon oxynitride layer is directly contacting the amorphous carbon layer.

21. The apparatus of claim 20, wherein the masking structure further comprises a photoresist layer, wherein the photoresist layer is directly contacting the hydrogenated silicon oxynitride layer.

39. The apparatus of claim 1, wherein the device structure includes a layer of a non-conducting material.

40. The apparatus of claim 39, wherein the device structure further includes a layer of a conducting material.

22. A mask structure for a device, the mask structure comprising:

an amorphous carbon layer formed over a semiconductor wafer, the semiconductor wafer including at least one alignment mark, wherein the amorphous carbon layer is transparent to radiation having wavelengths between 400 nanometers and 700 nanometers for allowing a reading of alignment marks in the semiconductor wafer in the wavelengths between 400 nanometers and 700 nanometers.

23. The mask structure of claim 22, wherein the amorphous carbon layer has an absorption coefficient between about 0.15 and about 0.001 at wavelength of 633 nanometers.

24. The mask structure of claim 22, wherein the amorphous carbon layer has a thickness of at least 4000 Angstroms.

25. The mask structure of claim 22 further comprising a photoresist layer.

26. The mask structure of claim 25 further comprising a cap layer formed over the amorphous carbon layer.

27. The mask structure of claim 26, wherein the cap layer includes silicon oxynitride.

28. The mask structure of claim 25, wherein the photoresist layer includes at least one opening.

29. The mask structure of claim 28, wherein the amorphous carbon layer includes at least one opening continuous with the at least one opening of the photoresist layer.

30. The mask structure of claim 22 further comprising an antireflective layer, and wherein the antireflective layer is directly contacting the amorphous carbon layer.

31. The mask structure of claim 22 further comprising a silicon oxide layer, wherein the silicon oxide layer is directly contacting the amorphous carbon layer.

32. The mask structure of claim 31 further comprising a photoresist layer, wherein the photoresist layer is directly contacting the silicon oxide layer.

33. The mask structure of claim 22 further comprising a hydrogenated silicon oxide layer, wherein the hydrogenated silicon oxide layer is directly contacting the amorphous carbon layer.

34. The mask structure of claim 33 further comprising a photoresist layer, wherein the photoresist layer is directly contacting the hydrogenated silicon oxide layer.

35. The mask structure of claim 22 further comprising a silicon oxynitride layer, wherein the silicon oxynitride layer is directly contacting the amorphous carbon layer.

36. The mask structure of claim 35 further comprising a photoresist layer, wherein the photoresist layer is directly contacting the silicon oxynitride layer.

37. The mask structure of claim 22 further comprising a hydrogenated silicon oxynitride layer, wherein the hydrogenated silicon oxynitride layer is directly contacting the amorphous carbon layer.

38. The mask structure of claim 37 further comprising a photoresist layer, wherein the photoresist layer is directly contacting the hydrogenated silicon oxynitride layer.