Plasma processing apparatus and electrode used therein
A plasma processing apparatus includes a depressurizable processing chamber; an electrode provided in the processing chamber; and a high frequency power supply for supplying a high frequency power into the processing chamber to thereby generating a plasma. Further, the electrode includes a base formed of a dielectric material; a dielectric body buried in the base and formed of the same dielectric material as the base; and a conductive adhesive layer provided in a bonding portion between the base and the dielectric body, the conductive adhesive layer bonding together and fixing the base and the dielectric body to each other.
1. A plasma processing apparatus comprising:
a depressurizable processing chamber;
an electrode provided in the processing chamber; and
a high frequency power supply for supplying a high frequency power into the processing chamber to thereby generate a plasma,
wherein the electrode includes;
a base formed of a dielectric material;
a dielectric body buried in the base and formed of the same dielectric material as the base; and
a conductive adhesive layer provided in a bonding portion between the base and the dielectric body, the conductive adhesive layer bonding and fixing the base and the dielectric body together, and
wherein the base includes a recess and the dielectric body is buried in the recess of the base.
2. The plasma processing apparatus of claim 1 , wherein the conductive adhesive layer is controlled to have a preset electric potential and an electric field intensity of the high frequency power is changed depending on a position on the dielectric body.
3. The plasma processing apparatus of claim 2 , wherein the conductive adhesive layer is controlled to have a ground potential.
4. The plasma processing apparatus of claim 1 , wherein the conductive adhesive layer is controlled to have a ground potential.
5. The plasma processing apparatus of claim 4 , wherein the recess has a tapered shape and is formed at a center of the base.
6. The plasma processing apparatus of claim 1 , wherein the conductive adhesive layer has resistivity of about 10 −6 to 10 −2 Ω·cm.
7. The plasma processing apparatus of claim 1 , wherein the base and the dielectric body are formed of one of alumina, silicon nitride, and aluminum nitride.
8. The plasma processing apparatus of claim 1 , wherein the electrode further includes a metal layer provided to cover the base, the metal layer being electrically connected to the conductive adhesive layer and having substantially the same potential as the conductive adhesive layer.
9. The plasma processing apparatus of claim 8 , wherein the electrode further includes one or more columnar conductive bodies provided to pass through the base, and the metal layer covers a top and a bottom surface of the base and is electrically connected to the columnar conductive bodies.
10. The plasma processing apparatus of claim 8 , further comprising one or more clamps provided to fix the base to the processing chamber at an outer side surface of the base, wherein the metal layer covers a top and a bottom surface of the base and is electrically connected to the clamps.
11. The plasma processing apparatus of claim 1 , wherein the dielectric body is patterned and provided at a position where a plasma density is high.
12. The plasma processing apparatus of claim 1 , wherein the dielectric body is arranged coaxially with the base.
13. The plasma processing apparatus of claim 1 , wherein the dielectric body has a thickness greater at a central portion than at a peripheral portion.
14. The plasma processing apparatus of claim 1 , wherein the dielectric body has a tapered shape.
15. The plasma processing apparatus of claim 1 , further comprising a facing electrode disposed to face the electrode in the processing chamber, wherein the high frequency power is applied to the electrode or the facing electrode, and a target object is mounted on the electrode or the facing electrode.
16. The plasma processing apparatus of claim 1 , a plasma side surface of the electrode is covered by a consumable top plate, the consumable top plate being exchangeable.
17. The plasma processing apparatus of claim 1 , wherein the electrode serves as an upper electrode and the upper electrode includes a plurality of gas inlet lines penetrating therethrough.
18. The plasma processing apparatus of claim 17 , wherein the electrode further includes a gas diffusion portion diffusing a gas and communicating with the gas inlet lines, the gas diffusion portion being provided above the dielectric body in the base.
19. An electrode for use in a depressurizable processing chamber of a plasma processing apparatus configured to introduce a processing gas into the depressurizable processing chamber, generating a plasma by supplying a high frequency power to the processing chamber, and performing plasma processing on a target object, the electrode comprising:
a base formed of a dielectric material;
a dielectric body buried in the base and formed of the same material as the base; and
a conductive adhesive layer provided between the base and the dielectric body to bond and fix therebetween,
wherein the base includes a recess and the dielectric body is buried in the recess of the base.
20. The electrode of claim 19 , further comprising a metal layer provided to cover the base, the metal layer being electrically connected to the conductive adhesive layer and having substantially the same potential as the conductive adhesive layer.