Patent ID: 12237204

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Hereinafter, the present disclosure will be described in detail with reference to the accompanying drawings. Herein, like components in each drawing are denoted by like reference numerals if possible. In addition, detailed descriptions of already known functions and/or configurations will be omitted. In the following description, components necessary for understanding operations according to various embodiments will be mainly described, and descriptions of elements that may obscure the gist of the description will be omitted. In addition, some elements in the drawings may be exaggerated, omitted, or schematically illustrated. The size of each component does not entirely reflect the actual size. Therefore, the descriptions provided herein are not limited by the relative sizes or spacings of the components drawn in each drawing.

In describing the embodiments of the present disclosure, when a detailed description of the known technology related to the present disclosure is determined to unnecessarily obscure the subject matter of the present disclosure, the detailed description will be omitted. In addition, terms to be described later are defined in consideration of functions in the present disclosure, and may vary according to the intention, custom, or the like of a user or operator. Therefore, the definitions of the terms should be made based on the description throughout this specification. Terms used in the detailed description are only for describing the embodiments of the present disclosure, and should not be construed as limiting in any way. Unless expressly used otherwise, singular expressions include the meanings of plural expressions. As used herein, expressions such as “including” or “comprising” are intended to indicate any features, numbers, steps, operations, elements, or some or combinations thereof, and should not be construed to exclude the existence or possibility of one or more other features, numbers, steps, operations, elements, or some or combinations thereof, in addition to those described above.

In addition, terms such as “first” and “second” may be used to describe various components, but the components are not limited by the terms, and these terms are only used for the purpose of distinguishing one component from another.

First, in the present disclosure, the ceramic susceptor is a semiconductor device for processing a substrate to be processed for various purposes such as a semiconductor wafer, a glass substrate, and a flexible substrate. the ceramic susceptor may include an electrostatic chuck electrode to be used as an electrostatic chuck to support a substrate to be processed, or may include a heating wire (or heating element) to heat the substrate to be processed to a predetermined temperature. Alternatively, the ceramic susceptor may include an RF electrode additionally or instead of the heating wire for processing such as plasma enhanced chemical vapor deposition on a substrate to be processed.

Therefore, in the following description, a conductor (or electrode) to be mentioned below will be described by taking the heating wire (or heating element) as an example, but is not limited thereto. It should be noted in advance that the conductor (or electrode) may also be directly applied to the RF electrode or the electrostatic chuck electrode.

For example, the heating wire (or heating element) as the conductor (or electrode) may be provided in the form of a plate-shaped coil or a flat plate using a resistance wire having a predetermined resistance. In addition, the heating wire (or heating element) may be fabricated in a multi-layer structure for precise temperature control. The heating wire (or heating element) may be supplied with power to perform a function of heating a substrate located on the upper surface of the ceramic susceptor to a predetermined temperature to smoothly perform vapor deposition and etching processes in a semiconductor manufacturing process.

In addition, for example, the electrostatic chuck electrode or RF electrode as the conductor (or electrode) is made of a conductive metal material, such as silver (Ag), gold (Au), nickel (Ni), tungsten (W), molybdenum (Mo), titanium (Ti), or an alloy thereof. In a semiconductor manufacturing process, the electrostatic chuck electrode may receive a power bias to generate electrostatic force, thereby executing chucking of a substrate placed on the upper surface of the ceramic susceptor. When unloading the substrate, the electrostatic chuck electrode may receive an opposite bias to be discharged, thereby executing dechucking of the substrate. In the semiconductor manufacturing process, the RF electrode may receive power to enable processing such as plasma-enhanced chemical vapor deposition on the substrate located on the upper surface of the ceramic susceptor.

A ceramic susceptor1000of the present disclosure includes a base body (1100inFIG.3) including a lower plate (210inFIG.3) and an upper plate (220inFIG.3) bonded to each other, an insulating plate (1200inFIG.3) bonded onto the base body, and conductors (or electrodes)1210and1220described above are disposed/buried in the insulating plate (1200inFIG.3).

Hereinafter, with reference toFIGS.2A to2CandFIGS.3to5, a method of manufacturing the ceramic susceptor1000according to an embodiment of the present disclosure and the structure of the ceramic susceptor1000manufactured thereby will be described in detail.

FIGS.2A to2Care cross-sectional views of lower and upper plates of a base body for explaining a method of manufacturing a ceramic susceptor according to an embodiment of the present disclosure.

Referring toFIG.2A, in order to manufacture the ceramic susceptor1000according to an embodiment of the present disclosure, first, a first active layer321, a first aluminum layer332, and a brazing filler layer323are sequentially laminated on the bonding surface of an upper plate220, i.e., one side surface of the upper plate220.

In addition, referring toFIG.2B, a second active metal layer311and a second aluminum layer312are sequentially laminated on the bonding surface of the lower plate210, that is, the substrate other than a groove211(seeFIG.4), which will form a cooling channel (215inFIG.3) of the lower plate210.

In addition, referring toFIG.2C, a base body1100of the ceramic susceptor1000of the present disclosure configured as a bonded body of the lower plate210and the upper plate220is manufactured by brazing-bonding the lower plate210and the upper plate220with the brazing filler layer323.

For the brazing-bonding, the conductive filler of the brazing filler layer323is capable of bonding the lower plate210and the upper plate220to each other by bringing the lower plate210and the upper plate220into close contact with each other, then heating the lower plate210and the upper plate220to a high temperature, and then cooling the lower plate210and the upper plate220. For example, Au—Ni metal filler, Al-based metal filler, or the like may be used as the conductive filler of the brazing filler layer323. One side of the upper plate220is bonded to the lower plate210, and as illustrated inFIG.5, holes225corresponding to holes in the insulating plate (1200inFIG.3) are provided in other side of the upper plate220to be connected to a channel for providing cooling gas or the like, and may be configured to provide cooling gas over the insulating plate (1200inFIG.3) as needed.

The above-described lower plate210and upper plate220are made of metal ceramic composite material, that is, an MMC of Al-ceramic composite powder, in order to prevent deformation from occurring, especially against low temperature deformation due to changes in the extreme process environment. For example, the lower plate210and the upper plate220may be made of a powder of, for example, a composite of Al with SiC, Si, boron (B), alumina (Al2O3), graphite, and the like.

In addition, the first active metal layer321of the upper plate220and the second active metal layer311of the lower plate210may contain one of Ti, Zr, Nb, Hf, and Ta, or an alloy thereof, and may have a thickness of 1 to 5 μm.

In addition, the first aluminum layer322of the upper plate220and the second aluminum layer312of the lower plate210may have a thickness of 5 to 10 μm.

The first active metal layer321of the upper plate220and the second active metal layer311of the lower plate210are capable of improving bondability by being melted together with the conductive filler, the first aluminum layer322, and the second aluminum layer312during the brazing-bonding. At interfaces with different physical and chemical properties, an oxidation-reduction reaction is capable of occurring to improve the bondability of both sides to form an interfacial product (see “Bonding of Ceramic and Metal Using Active Metal Brazing”, Journal of the Microelectronics&Packaging Society, Vol. 18, No. 3, p. 1-7).

When the base body1100is obtained through the method of manufacturing the ceramic susceptor1000according to an embodiment of the present disclosure as described above, the ceramic susceptor1000according to an embodiment of the present disclosure may be manufactured by bonding the base body with the insulating plate1200.

FIG.3is a view to be referred to explain a structure of bonding the insulating plate1200to the base body1100of the ceramic susceptor1000according to an embodiment of the present disclosure.

Referring toFIG.3, the ceramic susceptor1000according to an embodiment of the present disclosure includes the base body1100including the lower plate210and the upper plate220, and the insulating plate1200bonded thereon.

Conductors (or electrodes)1210and1220are disposed/buried in the above-described insulating plate1200. As described above, the ceramic susceptor1000is a semiconductor device for processing substrates to be processed for various purposes such as a semiconductor wafer, a glass substrate, and a flexible substrate, in which the conductors (or electrodes)1210and1220may be electrostatic chuck electrodes to be used as an electrostatic chuck for supporting a substrate to be processed, heating wires (or heating elements) for heating the substrate to be processed to a predetermined temperature, RF electrodes used for processing the substrate to be processed through plasma enhanced chemical vapor deposition, or the like.

The base body1100includes a cooling channel215formed by the groove211through brazing-bonding of the lower plate210and the upper plate220with the brazing filler layer323. The cooling channel215is a channel for the circulation of coolant, such as cooling water or cooling oil, and the coolant may be circulated through the cooling channel215in order to maintain the temperature of the ceramic susceptor1000at a predetermined level during the semiconductor process.

Meanwhile, bonding portions230and240of the upper and lower plates210and220are formed around the bonding channel215, that is, between two bonding channels215, and the bonding portions230and240between the lower and upper plates210and220may include an upper bonding portion240including a first active metal layer321, a first aluminum layer322, and a brazing filler layer323sequentially laminated on the upper plate220, and a lower plate bonding portion230including a second active metal layer311and a second aluminum layer312sequentially laminated on the lower plate210. The lower plate210and the upper plate220are brazing-bonded with the brazing filler layer323.

EXAMPLES

Table 1 below shows results obtained regarding leakage of He gas and cooling water for manufactured base bodies1100depending on whether or not active metal layers321and323and aluminum (Al) layers312and322were applied (applied: O, not applied: X) as surface treatment conditions of the bonding portions230and240when the MMC lower and upper plates210and220were used and an Al series metal filler was applied to the brazing filler layers323.

TABLE 1Examination results(He gas leakage standard:Surface treatment1.0E−04 (mbar * l/s) or more)conditionHe gasCommon conditionActiveAlleakageCollingTypeMaterialFillermetal layerlayer(mbar * l/s)water resultsBonding1MMCAl seriesXX1.0E−03OPoor2MMCAl seriesOX1.0E−04OPoor3MMCAl seriesOO2.0E−08xGood

As shown in Table 1 above, in the case where the active metal layers311and321and aluminum (Al) layers312and322were not applied, and the case where the active metal layers311and321were applied but the aluminum (Al) layers312and322were not applied, the defect in which coolant leaked and the defect in which He gas leakage occurred from the bonding portions at a level equal to or higher than the He gas leakage standard of 1.0E-04 (mbar*l/s) were confirmed. However, as in the present disclosure, when the MMC lower and upper plates210and220were used, and as the surface treatment conditions for the bonding portions230and240, the active metal layers311and321and aluminum (Al) layers312and322were all applied and brazing-bonded, it was confirmed that the bonding portions230and240were excellently bonded to each other, so there was no leakage of cooling water, and an improvement was obtained in which the gas leakage was reduced to a negligible level below the He gas leakage standard of 1.0E-04 (mbar*l/s).

Table 2 below shows comparison results of defect rates of manufactured base bodies1100depending on whether or not active metal layers321and323and aluminum (Al) layers312and322were applied (applied: O, not applied: X) as surface treatment conditions of the bonding portions230and240when the MMC lower and upper plates210and220were used and an Al series metal filler was applied to the brazing filler layers323.

TABLE 2Surface treatmentProduct manufacturing resultsconditionDefectAverageActiveAlratedefect rateTypemetal layerlayerQtyGoodPoor(%)(%)1XX62467772OX716883OO66000

As shown in Table 2 above, in the case where the active metal layers311and321and aluminum (Al) layers312and322were not applied, and the case where the active metal layers311and321were applied but the aluminum (Al) layers312and322were not applied, the defect rate for the defect in which coolant leaked and the defect in which He gas leakage occurred from the bonding portions at a level equal to or higher than the He gas leakage standard of 1.0E-04 (mbar*l/s) was 77% on average.

However, as in the present disclosure, when the MMC lower and upper plates210and220were used, and as the surface treatment conditions for the bonding portions230and240, the active metal layers311and321and the aluminum Al layers312and322were all applied and brazing-bonded, the bonding portions230and240were excellently bonded to each other, so the defect rate was zero.

As described above, in the ceramic susceptor according to the present disclosure and its manufacturing method, by applying multi-layer (active metal layer and aluminum layer) surface treatment between each of the upper and lower plates220and210of the base body and the brazing filler, the bonding strength between the upper plate220and the lower plate210of the MMC base body1100can be improved. As a result, it is possible to reduce the leak rate of He gas or the like during a process within semiconductor equipment so that the degree of vacuum can be increased, and to reduce leaking of coolant in a cooling channel, thereby contributing to improving yield by maintaining a stable process. In the example, it was confirmed that the He gas leak rate was lowered from the previous 1.0E-03 (mbar*l/s) to the level of 2.0.E-08 (mbar*l/s) after improvement.

In the foregoing, the present disclosure has been described based on specific details, such as specific components, limited embodiments, and drawings, but these are only provided to help a more general understanding of the present disclosure, and the present disclosure is not limited to the above-described embodiments. A person ordinarily skilled in the art to which the present disclosure pertains may make various modifications and changes without departing from the essential characteristics of the present disclosure. Therefore, the spirit of the present disclosure should not be limited to the described embodiments, and not only the appended claims, but also all technical ideas that are equivalent to or equivalently modified to the claims should be interpreted as being included in the scope of the present disclosure.