TW201338090A - Electrostatic sucking disc - Google Patents

Abstract

The present invention discloses an electrostatic sucking disc comprising an upper surface. An electrode is arranged inside the electrostatic sucking disc. The distances between the electrode and the upper surface of the electrostatic sucking disc are different. The electrode simultaneously connects to a DC power source and a radio frequency power source. The present invention can compensate etching/deposition rates of edge at the electrostatic sucking disc, so as to ensure effectiveness of the electrostatic sucking disc.

Description

Electrostatic chuck

The present invention relates to an electrostatic chuck, and more particularly to an electrostatic chuck having a different distance from an internal electrode of the electrostatic chuck to an upper surface of the electrostatic chuck.

The edge effect of semiconductor process parts is a problem that plagues the semiconductor industry. The edge effect of the semiconductor process component means that during the plasma processing, since the plasma is controlled by the electric field, the field strength at the edges of the upper and lower poles is affected by the outside, and a part of the electric field lines are always bent, resulting in field strength at the edge of the electric field. The unevenness causes the plasma concentration of the portion to be uneven. In this case, there is also a circle of uneven processing around the produced semiconductor process member.

Since the semiconductor process piece is circular, the larger the outer ring area, the poor uniformity of the various process steps at the edge portion will result in a significant drop in yield. Today, the 300mm process is commonly used, and the edge effect of semiconductor process parts is even more enormous.

Therefore, the industry needs to be able to simply and effectively improve edge effects and improve process uniformity.

It is an object of the present invention to provide an electrostatic chuck that compensates for the etching/deposition rate of the edge of the electrostatic chuck to ensure the effectiveness of the electrostatic chuck.

In order to achieve the above object, the present invention is achieved by the following technical solutions: The present invention provides an electrostatic chuck, the electrostatic chuck includes an upper surface, the electrostatic chuck is internally provided with an electrode, and the electrode is applied to the upper surface of the electrostatic chuck The distance is not Similarly, the electrodes are connected to a DC power source and an RF power source at the same time.

The electrode is divided into a plurality of ring electrodes, and the plurality of ring electrodes are arranged in a stepwise manner in the electrostatic chuck, and the plurality of ring electrodes are electrically connected in sequence.

The plurality of ring electrodes are arranged concentrically.

The plurality of ring electrodes have different diameters from each other.

The distance of the plurality of ring electrodes from the upper surface of the electrostatic chuck decreases as the diameter of the ring electrode increases.

The distance of the plurality of ring electrodes from the upper surface of the electrostatic chuck increases as the diameter of the ring electrode increases.

The internal electrode of the electrostatic chuck has a tapered shape, and the distance of the tapered electrode from the upper surface of the electrostatic chuck decreases as the diameter of the tapered electrode increases.

The internal electrode of the electrostatic chuck has a tapered shape, and the distance of the tapered electrode from the upper surface of the electrostatic chuck increases as the diameter of the tapered electrode increases.

The electrostatic chuck comprises a plurality of dielectric layers, each of the ring electrodes is disposed in each of the different dielectric layers, and the dielectric materials of the respective dielectric layers are different from each other.

The height of each of the dielectric layers is not more than 0.5 mm.

Compared with the prior art, the present invention adjusts the plasma concentration above the electrostatic chuck by setting the distance between the internal electrodes of the electrostatic chuck and the upper surface of the electrostatic chuck, thereby compensating for the etching/deposition rate of the edge of the electrostatic chuck, and realizing the generation. Uniform processing of the processed substrate.

100‧‧‧ Plasma processing room

1‧‧‧ ring electrode

2‧‧‧Dielectric layer

3‧‧‧ lower electrode

4‧‧‧High voltage DC power supply

5‧‧‧RF power source

10‧‧‧Electrostatic suction cup

11‧‧‧Substrate

1 is a schematic structural view of a plasma processing chamber in which an electrostatic chuck of the present invention is located; FIG. 2 is a schematic structural view showing an embodiment of an electrostatic chuck provided with a step electrode according to the present invention; The structure of the second embodiment of the electrostatic chuck of the electrode is schematically illustrated 4 is a schematic structural view of a third embodiment of an electrostatic chuck provided with a step electrode according to the present invention; FIG. 5 is a schematic structural view of a fourth embodiment of an electrostatic chuck provided with a tapered electrode according to the present invention; A schematic structural view of a fourth embodiment of an electrostatic chuck provided with a tapered electrode according to the present invention.

The present invention will be further described below in detail with reference to the accompanying drawings.

As shown in FIG. 1 to FIG. 4, an electrostatic chuck 10 provided with a step electrode, the upper support tape processing substrate 11 includes: a plurality of ring electrodes 1, and the plurality of ring electrodes 1 are arranged in a stepped manner on the electrostatic chuck 10 The plurality of ring electrodes 1 are electrically connected in sequence, and the adjacent ring electrodes 1 may be connected together by a circuit, or the ring electrodes 1 may be electrically connected in sequence by other means such as a metal piece. In various embodiments of the present invention, the plurality of ring electrodes 1 are concentrically arranged and different in diameter from each other, and thus the plurality of ring electrodes 1 constitute a stepped layout extending from the center to the edge of the electrostatic chuck 10.

One of the examples:

As shown in FIG. 1 and FIG. 2, the distance between the plurality of ring electrodes 1 from the upper surface of the electrostatic chuck 10 decreases as the diameter of the ring electrode 1 increases, and thus, a plurality of ring electrodes 1 form a center. The stepped layout with low and high edges, the plurality of ring electrodes 1 are electrically connected in sequence, and a high voltage direct current power source (such as 700V) and a radio frequency current are introduced into the electrostatic chuck 10 through the circuit.

The greater the distance from the upper surface of the electrostatic chuck 10, the greater the thickness of the dielectric material of the cylindrical portion of each of the ring electrode 1 and the upper surface of the electrostatic chuck 10, between the ring electrode 1 and the upper surface of the electrostatic chuck 10. The smaller the equivalent capacitance, the high voltage DC power supply 4 and the RF The less the power source 5 passes through, the lower the plasma concentration produced, and the lower the corresponding etch rate.

Therefore, after the high-voltage DC power source 4 and the RF power source 5 are introduced into the electrostatic chuck 10, the plasma concentration of the lower electrode 3 in the base of the electrostatic chuck 10 in the plasma processing chamber 100 is caused by the stepped annular electrode 1 in the present embodiment. Inhomogeneity, the problem that the intermediate concentration in the capacitively coupled plasma processing chamber is higher than the edge portion is improved, and the plasma concentration of the edge portion is compensated. By changing the distance between the ring electrode 1 and the upper surface of the electrostatic chuck 10, the final adjustment is obtained. The optimum compensation plasma concentration causes the lower electrode 3 of the plasma processing chamber 100 to be superimposed with the electric field generated by the ring electrode 1 in the electrostatic chuck 10 to produce a uniform plasma concentration distribution, which ensures the etching/deposition rate of the edge of the electrostatic chuck 10. Rising, compensating for the etching/deposition rate of the edge of the electrostatic chuck 10.

Embodiment 2:

As shown in FIG. 1 and FIG. 3, the distance between the plurality of ring electrodes 1 from the upper surface of the electrostatic chuck 10 increases as the diameter of the ring electrode 1 increases, and thus, the plurality of ring electrodes 1 form a center height and an edge. In a low stepped layout, the plurality of ring electrodes 1 are electrically connected in sequence, and a high voltage DC power source 4 and an RF power source 5 are introduced into the electrostatic chuck 10 through a circuit.

The greater the distance from the upper surface of the electrostatic chuck 10, the greater the thickness of the dielectric material of the cylindrical portion of each of the ring electrode 1 and the upper surface of the electrostatic chuck 10, between the ring electrode 1 and the upper surface of the electrostatic chuck 10. The smaller the equivalent capacitance, the less the high voltage DC power supply 4 is isolated, and the lower the etch rate of the corresponding edge region.

In the inductively coupled plasma processing chamber, since the plasma concentration generated is low in the middle and the edge is high, the stepped ring electrode with a high center and a low edge as described in the embodiment is used to solve the plasma distribution well. The problem of unevenness.

Third embodiment:

As shown in FIG. 1 and FIG. 4, in the embodiment, a plurality of ring electrodes 1 respectively The dielectric materials of each of the dielectric layers 2 are different from each other in the different dielectric layers 2, and the height of each of the dielectric layers 2 is not more than 0.5 mm. Different dielectric materials have different dielectric constants, and therefore, the same effects as those of the embodiment and the second embodiment are obtained, that is, the equivalent capacitance between the ring electrode 1 and the upper surface of the electrostatic chuck 10 is changed, thereby The plasma concentration of the lower electrode in the base of the original electrostatic chuck 10 is uneven, and the problem that the intermediate concentration is higher than the edge portion is improved, the plasma concentration of the edge portion is compensated, and the medium material is finally adjusted to obtain an optimum. The plasma concentration is compensated such that the electric field generated by the lower electrode 3 in the base and the ring electrode 1 in the electrostatic chuck 10 is superimposed to produce a uniform plasma concentration distribution, which ensures an increase in the etching/deposition rate of the edge of the electrostatic chuck 10, compensating for the electrostatic chuck 10 The etching/deposition rate of the edge.

Embodiment 4:

As shown in FIG. 1, FIG. 5 and FIG. 6, the internal electrode 1 of the electrostatic chuck 10 has a conical shape, and FIG. 5 shows that the distance from the tapered electrode 1 to the upper surface of the electrostatic chuck 10 decreases as the diameter of the ring electrode 1 increases. Small, thereby forming a conical structure with a low center and a high edge as shown in FIG. 5, which is connected to the high voltage direct current power source 4 and the radio frequency power source 5 at the same time.

The greater the distance from the upper surface of the electrostatic chuck 10, the greater the thickness of the dielectric material between the electrode and the upper surface of the electrostatic chuck, and the smaller the equivalent capacitance between the ring electrode 1 and the upper surface of the electrostatic chuck, the high voltage DC The less the power source 4 is isolated, the lower the corresponding etch rate.

With the technical solution described in this embodiment, the problem that the intermediate concentration in the capacitively coupled plasma processing chamber is higher than the edge portion is improved, and the plasma concentration of the edge portion is compensated by changing the upper surface of the ring electrode 1 and the electrostatic chuck 10 The distance is finally adjusted to obtain an optimum compensated plasma concentration such that the lower electrode 3 of the plasma processing chamber 100 is superimposed with the electric field generated by the ring electrode 1 in the electrostatic chuck 10 to produce a uniform plasma concentration distribution, which ensures the electrostatic chuck 10 The edge of the etch/deposition rate rises to compensate for the edge of the electrostatic chuck 10 Etching/deposition rate.

Similarly, similar to that shown in FIG. 6 , in the inductively coupled plasma processing chamber, since the plasma concentration generated is low in the middle and the edge is high, the cone electrode having a center height and a low edge as described in FIG. 6 is used. A good solution to this problem of uneven plasma distribution is solved.

In summary, the present invention relates to an electrostatic chuck capable of compensating for the etching/deposition rate of the edge of the electrostatic chuck, thereby ensuring the effectiveness of the electrostatic chuck.

Although the present invention has been described in detail by the preferred embodiments thereof, it should be understood that the foregoing description should not be construed as limiting. Various modifications and alterations of the present invention will be apparent to those skilled in the art. Therefore, the scope of the invention should be defined by the appended claims.

1‧‧‧ ring electrode

Claims (10)

An electrostatic chuck includes an upper surface, wherein an electrostatic chuck is internally provided with an electrode, and the electrode has a different distance from an upper surface of the electrostatic chuck, and the electrode is simultaneously connected to a DC power source and a RF power source. The electrostatic chuck according to claim 1, wherein the electrode is divided into a plurality of ring electrodes, and the plurality of ring electrodes are arranged in a stepwise manner in the electrostatic chuck, and the plurality of ring electrodes are electrically connected in sequence. The electrostatic chuck of claim 2, wherein the plurality of ring electrodes are arranged concentrically. The electrostatic chuck according to claim 2 or 3, wherein the plurality of ring electrodes have different diameters from each other. The electrostatic chuck according to claim 4, wherein the distance of the plurality of ring electrodes from the upper surface of the electrostatic chuck decreases as the diameter of the ring electrode (1) increases. The electrostatic chuck according to claim 4, wherein the distance of the plurality of ring electrodes (1) from the upper surface of the electrostatic chuck increases as the diameter of the ring electrode (1) increases. The electrostatic chuck according to claim 1, wherein the internal electrode of the electrostatic chuck has a tapered shape, and a distance of the tapered electrode from an upper surface of the electrostatic chuck decreases as a diameter of the tapered electrode increases. The electrostatic chuck according to claim 1, wherein the internal electrode of the electrostatic chuck is tapered. The distance of the tapered electrode from the upper surface of the electrostatic chuck increases as the diameter of the tapered electrode increases. The electrostatic chuck of claim 2, wherein the electrostatic chuck comprises a plurality of dielectric layers (2), each of the ring electrodes (1) being disposed in each of the different dielectric layers (2), The dielectric materials of the respective dielectric layers (2) are different from each other. The electrostatic chuck of claim 9, wherein the height of each of the dielectric layers (2) is no more than 0.5 mm.