Substrate holding unit and substrate processing apparatus

1 . A substrate support unit, comprising:

a ceramic body having a surface for supporting a substrate, and including aluminum nitride (AlN);

a heat generating resistor disposed in the ceramic body, and including molybdenum (Mo); and

a coating layer surrounding the heat generating resistor, and including molybdenum aluminum nitride (MoAlN),

wherein the coating layer includes a plurality of layers having different molybdenum (Mo) concentrations.

2 . The substrate support unit as claimed in claim 1 , wherein:

the ceramic body includes an inner region and an outer peripheral region surrounding the inner region,

the heat generating resistor includes a first heat generating resistor arranged in the inner region, and

the heat generating resistor includes a second heat generating resistor separated from the first heat generating resistor and arranged in the outer peripheral region.

3 . The substrate support unit as claimed in claim 2 , wherein:

the coating layer includes a first coating layer surrounding the first heat generating resistor,

the coating layer includes a second coating layer surrounding the second heat generating resistor, and

the first coating layer has a thickness greater than a thickness of the second coating layer.

4 . The substrate support unit as claimed in claim 2 , wherein:

the coating layer includes a first coating layer surrounding the first heat generating resistor,

the coating layer includes a second coating layer surrounding the second heat generating resistor, and

the first coating layer has a composition different from a composition of the second coating layer.

5 . The substrate support unit as claimed in claim 1 , further comprising:

an additional coating layer surrounding the coating layer,

wherein the additional coating layer includes aluminum nitride doped with a diffusion preventing element, and

wherein the diffusion preventing element includes at least one element from a group of Be, B, C, N, Mg, P, S, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, and As.

6 . The substrate support unit as claimed in claim 5 , wherein the additional coating layer includes magnesium (Mg)-doped aluminum nitride.

7 . The support substrate unit as claimed in claim 1 , wherein the coating layer has a molybdenum (Mo) concentration in a range of 0.5 wt % to 10 wt %.

8 . The substrate support unit as claimed in claim 1 , wherein the coating layer has a molybdenum concentration gradually increasing toward an inside of the coating layer.

9 . The substrate support unit as claimed in claim 1 , wherein the plurality of layers includes:

a first layer surrounding the heat generating resistor and containing molybdenum (Mo) of a first concentration, and

a second layer surrounding the first layer and containing molybdenum (Mo) of a second concentration that is lower than the first concentration.

10 . The substrate support unit as claimed in claim 1 , wherein:

the plurality of layers includes a first layer including molybdenum (Mo) of a first concentration and a second layer including molybdenum (Mo) of a second concentration different from the first concentration, and

the first layer and the second layer are stacked.

11 . The substrate support unit as claimed in claim 1 , further comprising:

an outer coating layer,

wherein the ceramic body includes an inner region and an outer peripheral region surrounding the inner region,

wherein the heat generating resistor includes first and second heat generating resistors respectively disposed in the inner region and the outer peripheral region of the ceramic body, and separated from each other,

wherein the outer coating layer surrounds each of the first and second heat generating resistors, the outer coating layer including a same material as the ceramic body, doped with a diffusion preventing element selected from a group of Be, B, C, N, Mg, P, S, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, and As.

12 . A substrate support unit, comprising:

a ceramic body having a surface for supporting a substrate, and including an inner region and an outer peripheral region surrounding the inner region, the ceramic body including a ceramic material;

a first heat generating resistor disposed within the ceramic body in the inner region and a second heat generating resistor disposed within the ceramic body in the outer peripheral region, each of the first and second heat generating resistors having a wire structure;

first and second inner coating layers directly contacting outer surfaces of the first and second heat generating resistors, respectively, the first and second inner coating layers including a material the same as a material of the ceramic body; and

first and second outer coating layers surrounding the first and second inner coating layers, respectively, the first and second outer coating layers including aluminum nitride,

wherein when viewed in cross-section, the first and second inner coating layers concentrically surround the first and second heat generating resistors, respectively, and the first and second outer coating layers concentrically surround the first and second inner coating layers, respectively.

13 . The substrate support unit as claimed in claim 12 , wherein the first and second outer coating layers are doped with a diffusion preventing element selected from Be, B, C, N, Mg, P, S, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, and As.

14 . The substrate support unit as claimed in claim 12 , wherein the ceramic material includes aluminum nitride (AlN), alumina (Al 2 O 3 ), or silicon carbide (SiC).

15 . The substrate support unit as claimed in claim 12 , wherein at least one of the first and second heat generating resistors includes a metal or an alloy selected from a group of molybdenum (Mo), rhodium (Rh), palladium (Pd), tantalum (Ta), tungsten (W), platinum (Pt), a Ni—Cr alloy, a Fe—Cr alloy, a Fe—Cr—Al alloy, PtRh alloy, and a La—Cr alloy.

16 . The substrate support unit as claimed in claim 12 ,

wherein the ceramic body includes aluminum nitride (AlN),

wherein the first and second heat generating resistors include molybdenum (Mo),

wherein the first and second inner coating layers include molybdenum aluminum nitride (MoAlN).

17 . The substrate support unit as claimed in claim 16 , wherein each of the first and second inner coating layers has a molybdenum (Mo) concentration in a range of 0.5 wt % to 10 wt %.

18 . The substrate support unit as claimed in claim 16 , wherein each of the first and second inner coating layers has a thickness in a range of 10 μm to 100 μm.

19 . The substrate support unit as claimed in claim 12 , wherein each of the first and second outer coating layers has a thickness in a range of 5 μm to 50 μm.

20 . A substrate support unit, comprising:

a ceramic body having a first surface for supporting a substrate and a second surface opposite to the first surface, the ceramic body including aluminum nitride (AlN);

a heat generating resistor disposed in the ceramic body, and including molybdenum (Mo), the heat generating resistor having a wire structure;

a first inner coating layer surrounding the heat generating resistor and a second inner coating layer surrounding the first inner coating layer, each of the first and second inner coating layers including molybdenum (Mo); and

an outer coating layer surrounding the first and second inner coating layers, the outer coating layer including aluminum nitride doped with magnesium (Mg),

wherein when viewed in cross-section, the first inner coating layer concentrically surrounds the heat generating resistor and directly contacts an outer surface of the heat generating resistor, the second inner coating layer concentrically surrounds the first inner coating layer and directly contacts an outer surface of the first inner coating layer, and the outer coating layer concentrically surrounds the second inner coating layer and directly contacts an outer surface of the second inner coating layer.