Plasma processing system and apparatus and a sample processing method

• US 20010015175A1
• Filed: 02/21/2001
• Published: 08/23/2001
• Est. Priority Date: 02/21/2000
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Usui, Tatehito, Yamamoto, Hideyuki, Takahashi, Kazue, Masuda, Toshio, Suehiro, Mitsuru, Enami, Hiromichi, Kanekiyo, Hiroshi
• Granted Patent: US 6,755,932 B2
• Time in Patent Office: Days
• US Class Current: 118/723R
• CPC Class Codes: G01N 21/68 using high frequency electric fields
• CPC Class Codes: H01J 37/32082 Radio frequency generated discharge H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge
• CPC Class Codes: H01J 37/32972 Spectral analysis
• CPC Class Codes: H01L 21/67069 for drying etching

Abstract

The object of the present invention is to provide a plasma processing apparatus wherein plasma is generated in process chamber to treat a sample. Said plasma processing apparatus is further characterized in that multiple closely packed through-holes are formed on the plate installed on the UHF antenna arranged opposite to the sample, an optical transmitter is installed almost in contact with the back of the through-holes, and an optical transmission means is arranged on the other end of said optical transmitter, thereby measuring optical information coming from the sample and plasma through optical transmitter and optical transmission means by means of an measuring instrument. No abnormal discharge or particle contamination occur to through-holes even in long-term discharge process, and no deterioration occurs to the optical performance at the end face of the optical transmitter. Said plasma processing apparatus ensures stable and high precision measurement of the state of the surface of sample and plasma for a long time.

Claims

1. A plasma processing apparatus wherein process gas is supplied into a vacuum chamber, plasma is generated by a plasma generator and a sample placed on a sample bench is processed by said plasma;

said plasma processing apparatus further characterized in that p2 an optical reflector is arranged within said vacuum chamber,

at least one or more through-holes with depth-to-diameter ratios ranging from 5 up to 100 are formed at a position opposite to an optical reflector of said vacuum chamber, and

a means of measuring optical information from the surface state of said reflector via said through-hole is provided.

3. A plasma processing apparatus according to

claim 1

or

claim 2

further characterized in that the diameter of said through-hole is 0.1 mm to 5 mm.

4. A plasma processing apparatus according to any one of

claims 1

to

3

further characterized in that optical information from the surface state of said optical reflector is reflected or interfered light on the surface of said optical reflector of said plasma.

5. A plasma processing apparatus according to any one of

claims 1

to

4

further characterized in that said optical reflector is said sample placed on said sample bench.

6. A plasma processing apparatus according to any one of

claims 1

to

4

further characterized in that said optical reflector is installed on the wall face of said vacuum chamber.

7. A plasma processing apparatus according to any one of

claims 1

to

6

further characterized in that the total of the opening area of said through-hole is made 5 to 50% of the total area of the area in which a plural of said through-holes are formed.

8. A plasma processing apparatus according to any one of

claims 1

to

7

further characterized in that quartz or sapphire is used as said optical transmitter.

9. A plasma processing apparatus according to any one of

claims 1

to

8

further characterized in that said optical transmitter is fixed replaceably onto said vacuum chamber by only one set of holding means and vacuum sealing means.

2. A plasma processing apparatus wherein process gas is supplied into the vacuum chamber, plasma is generated by a plasma generator and a sample placed on a sample bench is processed by said plasma;

said plasma processing apparatus further characterized in that

an optical reflector is arranged within said vacuum chamber,

at least one or more through-holes with depth-to-diameter ratios ranging from 5 up to 100 are formed at a position opposite to said optical reflector of said vacuum chamber and on a structure in contact with said plasma,

an optical transmitter is installed on the back of said through-hole so that one end face thereof will be almost in contact with said structure,

an optical transmission means is laid out on the other end face of said transmitter, and

a means of measuring optical information from the surface state of said optical reflector measured via said optical transmitter and said optical transmission means is provided.

10. A plasma processing apparatus wherein process gas is supplied into a vacuum chamber, plasma is generated by a plasma generator and a sample placed on a sample bench is processed by said plasma;

said plasma processing apparatus further characterized in that

an optical reflector is arranged within said vacuum chamber,

at least one or more through-holes with depth-to-diameter ratios ranging from 5 up to 100 are formed at a position opposite to said optical reflector of said vacuum chamber,

a means of measuring optical information from the surface state of said reflector via said through-hole is provided, and

a means of determining whether some foreign substance has generated, based on the variations of said optical information is provided.

11. A plasma processing apparatus according to

claim 10

further characterized in that a display means of issuing a warning is provided when reflected or interfered light measured as said optical information has substantially changed.

12. A plasma processing apparatus wherein process gas is supplied into a vacuum chamber, plasma is generated by a plasma generator and a sample placed on a sample bench is processed by said plasma;

said plasma processing apparatus further characterized in that

an optical reflector is arranged within said vacuum chamber,

at least one or more through-holes with depth-to-diameter ratios ranging from 5 up to 100 are formed at a position opposite to said optical reflector of said vacuum chamber and on a structure in contact with said plasma,

a means of measuring optical information from the surface state of said reflector via said through-hole is provided, and

a means of determining to what extent the consumption of said structure has progressed, based on the variations of said optical information.

13. A plasma processing apparatus according to

claim 12

further characterized in that said structure is a silicon-made plate with high purity or a carbon-made plate.

14. A sample processing method whereof process gas is supplied into a vacuum chamber, plasma is generated by a plasma generator and a sample placed on a sample bench is processed by said plasma;

said sample processing method further characterized in that

said sample is formed on the wall of said vacuum chamber at a position opposite to said sample of said vacuum chamber,

optical information from the surface state of said sample is measured via at least one or more through-holes with depth-to-diameter ratios ranging from 5 up to 100, and

said sample is processed while measuring the state of the thin film of said sample surface based on the variations of said optical information.