TW201621971A - Heating element in inductively coupled plasma etching device and method of installing heating element - Google Patents

Abstract

The present invention discloses a heating element in an inductively coupled plasma (ICP) etching device and a method of installing the heating element. The heating element in the ICP etching device and the method of installing the heating element dispose an entire resistor wire element in layers. The resistor wire portion in each layer forms a resistor wire layer. A resistor wire connection portion connects the resistor wire portions in adjacent resistor wire layers. An insulating material layer is arranged between adjacent resistor wire layers. The resistor wire portions in all resistor wire layers are identical in shape and overlapped in the vertical direction. As a result, the area of a closed circuit infinitely approaches 0. This invention prevents an induced electro-motive force from being generated in the closed circuit formed in the heating element, greatly reducing the influence on the induced magnetic field generated by the sensing coil and improving the capacity and uniformity of heating.

Description

Heating component and heating component setting method in inductively coupled plasma etching element

The present invention relates to the field of semiconductor manufacturing, and in particular to a heating assembly and a heating assembly setting method in an inductively coupled plasma (ICP) etching element.

As shown in FIG. 1 , it is a schematic structural view of an inductively coupled plasma (ICP) etching element 1 including a planar spiral induction coil 2, and two ends of the induction coil 2 are connected to a radio frequency source by a lead 201. 3. The induction coil 2 generates an induced magnetic field under the excitation of the RF source 3 (the magnetic induction line 7 is indicated by a broken line in Fig. 1). The ceramic RF window 103 isolates the planar spiral induction coil 2 from the vacuum chamber 101. The vacuum chamber 101 is filled with a reactive gas. Under the action of the electromagnetic field, the gas discharge generates a plasma 102 to etch the semiconductor substrate 5. The heating assembly 4 includes a resistance wire 401 (shown in FIG. 2). The resistance wire 401 is disposed above the ceramic RF window 103 under the planar spiral induction coil 2, and the two ends of the resistance wire 401 are connected to the power source 6. As shown in Fig. 2, the input current Iin flows from the power source 6 into one end of the resistance wire 401, and the output current Iout flows out from the other end of the resistance wire back to the power source 6 to form a complete closed loop. The current is generated by the resistance wire 401 to heat the ceramic RF window 103 to maintain the vacuum chamber 101 at a constant temperature to provide uniformity and uniformity of the etch rate.

According to the law of cooling, the induced electromotive force generated in the closed coil is proportional to the magnetic field strength (magnetic flux) and the rate of change of the area of the closed region within the coil. The electric resistance wire 401 and the power source 6 in the heating assembly 4 of the inductively coupled plasma etching element 1 constitute a closed loop. During the etching process, although the area of the closed coil formed by the electric resistance wire 401 is fixed, there is no change, but due to the radio frequency The source 3 uses an alternating current RF source, so the direction of the induced magnetic field generated by the induction coil 2 changes as the direction of the current changes, which causes a change in the magnetic flux in the closed loop formed by the resistance wire 401, thereby generating an induced electromotive force and Inductive current, which further generates an induced magnetic field, and the direction of the induced magnetic field is opposite to the direction of the electromagnetic field generated by the induction coil 2, which cancels out that a part of the induction coil 2 is generated to pass down through the ceramic RF window 103 into the vacuum chamber. The electromagnetic field of 101, which leads to a significant reduction in coupling efficiency. The inductive current flowing through the resistance wire 401 also generates heat, and the generated heat is affected by the magnitude of the induced current, and finally the heat generated on the heating assembly 4 is controlled by the external heating source 6 and by the electromagnetic field generated by the induction coil 2. influences. The intensity of the electromagnetic field generated by the induction coil 2 needs to be arbitrarily set according to the needs of the plasma processing process, but the temperature distribution on the ceramic RF window 103 does require relatively stable control and cannot be rapidly changed, otherwise it will be cracked due to frequent thermal expansion shrinkage. . Therefore, the industry needs a technology that can avoid the interference of the electromagnetic field generated by the induction coil 2 on the heating assembly to achieve precise control of the temperature on the ceramic RF window.

The invention provides a heating component and a heating component setting method in an inductively coupled plasma (ICP) etching element, which can avoid generating an induced electromotive force in a closed loop formed by the heating component, and greatly reducing the influence of the induced magnetic field formed by the induction coil. Increased heating capacity and uniformity.

In order to achieve the above object, the present invention provides a heating assembly in an inductively coupled plasma etching element, the heating assembly being disposed in an inductively coupled plasma etching element, the inductively coupled plasma etching element comprising: an induction coil, an induction coil The two ends are connected to the RF source by wires, and the induction coil generates an induced magnetic field under the excitation of the RF source; the vacuum chamber, the reaction gas in the vacuum chamber generates plasma under the action of the induced magnetic field generated by the induction coil, and the semiconductor substrate is subjected to the semiconductor substrate. Etching; a ceramic RF window that isolates the induction coil from the vacuum chamber; the heating assembly includes a resistance wire assembly and an isolation assembly, the resistance wire assembly and the isolation assembly are disposed on the upper surface of the ceramic RF window, below the induction coil; the resistance wire assembly includes a plurality of layers of resistance wires arranged one above another, each layer of resistance wires forming a resistance wire layer; connecting a resistance wire connection portion of at least two resistance wire portions located in adjacent resistance wire layers; the isolation component comprising a plurality of disposed phases a layer of insulating material between adjacent resistive layers; a portion of the resistive wire on all of the resistive layers Same position in the vertical and coincident.

Preferably, the number M of the resistance wire layers is an even number, the number of the resistance wire connecting portions is N = M-1, and the number of the insulating material layers is L = N = M-1.

Preferably, the current inlet end of the resistance wire assembly is located in the first layer of the resistance wire, and the current outlet end of the resistance wire assembly is located in the last layer of the resistance wire; or the current inlet end of the resistance wire assembly is located in the last layer of the resistance wire, the resistor The current exit end of the wire assembly is located in the first layer of resistance wire.

Preferably, the heating assembly further comprises a power source connecting the current inlet end and the current outlet end of the resistance wire assembly.

The invention further provides a method for providing a heating assembly in an inductively coupled plasma etching element, the method comprising layering a complete resistance wire assembly, the resistance wire assembly being divided into a resistance wire portion and a resistance wire connection portion, and a resistance wire portion The plurality of layers are arranged one above another, each layer of the resistance wire forms a resistance wire layer, and the resistance wire connection portion connects at least two resistance wire portions located in the adjacent resistance wire layer, the method further comprises an isolation component, and the isolation component comprises a plurality of An insulating material layer between adjacent resistance wire layers; the layered resistance wire assembly satisfies the following conditions: the resistance wire portions on all the resistance wire layers have the same shape and the positions are vertically overlapped, and the area of the closed circuit of the resistance wire assembly is reduced. Approaching to 0.

Preferably, the number M of the resistance wire layers is an even number, the number of the resistance wire connecting portions is N = M-1, and the number of the insulating material layers is L = N = M-1.

Preferably, the current inlet end of the resistance wire assembly is located in the first layer of the resistance wire, and the current outlet end of the resistance wire assembly is located in the last layer of the resistance wire; or the current inlet end of the resistance wire assembly is located in the last layer of the resistance wire, the resistor The current exit end of the wire assembly is located in the first layer of resistance wire.

The invention further provides an inductively coupled plasma etching element, the inductively coupled plasma etching element comprises: an induction coil, wherein two ends of the induction coil are connected to a radio frequency source by a lead wire, and the induction coil generates an induced magnetic field under excitation of the radio frequency source; the vacuum chamber The reaction gas in the vacuum chamber generates plasma under the action of the induced magnetic field generated by the induction coil to etch the semiconductor substrate; the ceramic RF window separates the induction coil from the vacuum chamber; and the heating component is disposed in the inductor Coupling the plasma etching element; the heating component comprises a resistance wire assembly and an isolation component, the resistance wire assembly and the isolation component are disposed on the upper surface of the ceramic RF window, under the induction coil; and the resistance wire assembly comprises: a plurality of layers of the resistance wire arranged one above another And each layer of the resistance wire forms a resistance wire layer; a resistance wire connection portion connecting at least two resistance wire portions located in the adjacent resistance wire layer; the isolation component includes a plurality of insulation material layers disposed between the adjacent resistance wire layers The resistance wire portions on all the resistance wire layers have the same shape and the positions are vertically overlapped.

Preferably, the number M of the resistance wire layers is an even number, the number of the resistance wire connecting portions is N = M-1, and the number of the insulating material layers is L = N = M-1.

Preferably, the current inlet end of the resistance wire assembly is located in the first layer of the resistance wire, and the current outlet end of the resistance wire assembly is located in the last layer of the resistance wire; or the current inlet end of the resistance wire assembly is located in the last layer of the resistance wire, the resistor The current exit end of the wire assembly is located in the first layer of resistance wire.

Preferably, the heating assembly further comprises a power source connecting the current inlet end and the current outlet end of the resistance wire assembly.

The invention can avoid the generation of the induced electromotive force in the closed loop formed by the heating component, greatly reduce the influence on the induced magnetic field formed by the induction coil, and improve the heating ability and uniformity.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be specifically described based on the drawings 3 to 5.

As shown in FIG. 3, the inductively coupled plasma (ICP) etching element 1 includes an induction coil 2, and both ends of the induction coil 2 are connected to the RF source 3 by a lead 201, and the induction coil 2 is generated under the excitation of the RF source 3. Inductive magnetic field; vacuum chamber 101, reactive gas in vacuum chamber 101 generates plasma 102 under the action of induced magnetic field generated by induction coil 2, etches semiconductor substrate 5; ceramic RF window 103, which inductive coil 2 and vacuum The cavity 101 is isolated, the ceramic RF window 103 is flat or dome-shaped; the heating assembly 8 includes a resistance wire assembly 801 and a power supply 9 connected to both ends of the resistance wire assembly 801, and the resistance wire assembly 801 is disposed on the ceramic RF window 103. Above, located below the induction coil 2.

According to the law of cooling, the induced electromotive force generated in the closed coil is proportional to the magnetic field strength (magnetic flux) and the rate of change of the area of the closed region within the coil. In the inductively coupled plasma etching element 1, it is difficult to control the change in the magnetic flux in the closed loop formed by the resistance wire assembly 801, and if the area of the closed loop of the resistance wire assembly 801 can be minimized, the induced inductance can be reduced. The influence of the electromotive force and the induced current, if the area of the closed loop of the resistance wire assembly 801 can be reduced to approach 0, there is no induced electromotive force and induced current generated at all, and the induced magnetic field band generated for the induction coil 2 is not generated. Come to any impact.

According to the idea, the present invention provides a heating assembly 8 in an inductively coupled plasma etching element. The heating assembly 8 is disposed in an inductively coupled plasma etching element. The heating assembly 8 includes a resistance wire assembly 801 and an isolation assembly, and further includes a connection resistance wire. The current inlet end 83 of the assembly 801 and the power supply 9 of the current outlet end 84, the resistance wire assembly 801 and the isolation assembly are disposed on the ceramic RF window 103 below the induction coil 2.

As shown in FIG. 4, the resistance wire assembly 801 is a layered complete resistance wire, and the resistance wire assembly 801 comprises: a plurality of layers of resistance wire portions 81 stacked one above another, each layer of the resistance wire portion 81 forming a resistance wire layer; A resistance wire connecting portion 82 of at least two resistance wire portions 81 located in adjacent resistance wire layers is connected.

The isolation component includes a plurality of layers of insulating material disposed between adjacent ones of the resistance layers.

As shown in Fig. 5, the resistance wire portions 81 on all of the resistance wire layers are identical in shape and overlap in position, and the area of the closed loop of the resistance wire assembly 801 is reduced to approach zero.

The current inlet end 83 of the resistance wire assembly 801 is located in the first layer of resistance wire, the current outlet end 84 of the resistance wire assembly 801 is located on the last layer of resistance wire; or the current inlet end 83 of the resistance wire assembly 801 is located on the last layer of resistance wire The current exit end 84 of the resistance wire assembly 801 is located in the first layer of resistance wire.

The number M of the resistance wire layers is an even number, the number of the resistance wire connecting portions 82 is N = M-1, and the number of insulating material layers L = N = M-1.

As shown in FIG. 4, which is an embodiment of the present invention, the resistance wire assembly 801 is disposed on two resistance wire layers, and the resistance wire portions 81 on the two resistance wire layers have the same shape and are vertically aligned (as shown in FIG. 5). shown), the inlet end of the current resistive wire assembly 83 between the first layer 801 of the layer of the resistance wire, resistance wire assembly 801 of the outlet end of the current 84 in the second wire layer resistance layer, the input current I _in a current flows from the inlet end of the resistance wire 83 Component 801, output current _Iout returns from current outlet terminal 84 to power source 9.

By using the resistance wire assembly 801 provided by the invention, the area of the closed loop can be made infinitely close to zero, which avoids the generation of the induced electromotive force and the induced current, and does not have any influence on the induced magnetic field generated by the induction coil 2.

The invention further provides a heating component setting method in an inductively coupled plasma etching element, wherein a complete resistance wire assembly 801 is layered to form a resistance wire portion 81 and a resistance wire connecting portion 82, and the resistance wire portion 81 is layered up and down Arranged in a stack, each layer of the resistance wire portion 81 forms a resistance wire layer, the resistance wire connection portion 82 connects at least two resistance wire portions 81 located in the adjacent resistance wire layer, and further comprises an isolation component, the isolation component comprising a plurality of A layer of insulating material between adjacent layers of resistance wires.

It is necessary to ensure that the layered resistance wire assembly 801 satisfies the following conditions:

The resistance wire portions 81 on all of the resistance wire layers are identical in shape and are positioned one above the other, reducing the area of the closed loop of the resistance wire assembly 801 to approach zero. The current inlet end 83 of the resistance wire assembly 801 is located in the first layer of resistance wire, the current outlet end 84 of the resistance wire assembly 801 is located on the last layer of resistance wire; or the current inlet end 83 of the resistance wire assembly 801 is located on the last layer of resistance wire The current exit end 84 of the resistance wire assembly 801 is located in the first layer of resistance wire.

The number M of the resistance wire layers is an even number, the number of the resistance wire connecting portions 82 is N = M-1, and the number of insulating material layers L = N = M-1.

The invention further provides an inductively coupled plasma etching element, the inductively coupled plasma etching element comprises: an induction coil 2, two ends of the induction coil 2 are connected to the RF source 3 by a lead 201, and the induction coil 2 is excited by the RF source 3 An induced magnetic field is generated; the vacuum chamber 101, the reactive gas in the vacuum chamber 101 generates a plasma 102 under the action of an induced magnetic field generated by the induction coil 2, and etches the semiconductor substrate 5; the ceramic RF window 103, which inducts the coil 2 and The vacuum chamber 101 is isolated; the heating assembly 8 is disposed in the inductively coupled plasma etching element; the heating assembly 8 includes the resistance wire assembly 801 and the isolation assembly, and further includes a current inlet end 83 and a current outlet end that connect the resistance wire assembly 801 The power source 9, the resistance wire assembly 801 and the isolation assembly of 84 are disposed on the ceramic RF window 103 below the induction coil 2.

The resistance wire assembly 801 is a layered complete resistance wire, and the resistance wire assembly 801 comprises: a plurality of layers of resistance wire portions 81 arranged one above another, each layer of the resistance wire portion 81 forming a resistance wire layer; the connection is located adjacent to the resistance wire layer The resistance wires of the at least two resistance wire portions 81 are connected to the portion 82.

The isolation component includes a plurality of layers of insulating material disposed between adjacent ones of the resistance layers.

The resistance wire portions 81 on all of the resistance wire layers are identical in shape and are positioned one above the other, reducing the area of the closed loop of the resistance wire assembly 801 to approach zero.

The current inlet end 83 of the resistance wire assembly 801 is located in the first layer of resistance wire, the current outlet end 84 of the resistance wire assembly 801 is located on the last layer of resistance wire; or the current inlet end 83 of the resistance wire assembly 801 is located on the last layer of resistance wire The current exit end 84 of the resistance wire assembly 801 is located in the first layer of resistance wire.

The number M of the resistance wire layers is an even number, the number of the resistance wire connecting portions 82 is N = M-1, and the number of the insulating material layers is L = N = M-1.

Although the present invention has been described in detail by the above embodiments, it should be understood that the above description should not be construed as limiting. Various modifications and alterations of the present invention will be apparent to those skilled in the <RTIgt; Therefore, the scope of the invention should be limited by the scope of the appended claims.

1‧‧‧Inductively coupled plasma etched components
101‧‧‧vacuum chamber
102‧‧‧ Plasma
103‧‧‧Ceramic RF window
2‧‧‧Induction coil
201‧‧‧ lead
3‧‧‧RF source
4, 8‧‧‧ heating components
401‧‧‧resistance wire
5‧‧‧Semiconductor substrate
6, 9‧‧‧ power supply
7‧‧‧Magnetic line
801‧‧‧resist wire assembly
81‧‧‧resist wire part
82‧‧‧resist wire connection
83‧‧‧current inlet end
84‧‧‧current outlet

Figure 1 is a schematic view showing the structure of an inductively coupled plasma etching element in the prior art. Fig. 2 is a schematic view showing the arrangement of the electric resistance wires in the heating assembly in the prior art. Figure 3 is a schematic illustration of the structure of an inductively coupled plasma etched component comprising a heating assembly provided by the present invention. Figure 4 is a cross-sectional view of a resistance wire assembly in a heating assembly provided by the present invention. Figure 5 is a top plan view of a resistance wire assembly in a heating assembly provided by the present invention.

81‧‧‧resist wire part

82‧‧‧resist wire connection

83‧‧‧current inlet end

84‧‧‧current outlet

Claims (11)

A heating assembly in an inductively coupled plasma etch element, the heating assembly (8) being disposed in the inductively coupled plasma etch element (1), the inductively coupled plasma etch element (1) comprising: an induction coil (2), The two ends of the induction coil (2) are connected to a radio frequency source (3) by a lead wire (201). Under the excitation of the radio frequency source (3), the induction coil (2) generates an induced magnetic field; a vacuum chamber (101), The reaction gas in the vacuum chamber (101) generates a plasma (102) under the action of the induced magnetic field generated by the induction coil (2), and etches the semiconductor substrate (5); the ceramic RF window (103), which The induction coil (2) is isolated from the vacuum chamber (101); characterized in that the heating assembly (8) comprises a resistance wire assembly (801) and an isolation assembly, the resistance wire assembly (801) and the isolation assembly are disposed at The upper surface of the ceramic RF window (103) is located below the induction coil (2); the resistance wire assembly (801) comprises: a plurality of resistor wire portions (81) arranged one above another, each layer of the resistance wire portion (81) Form resistor a resistor wire connecting portion (82) connecting at least two of the resistance wire portions (81) located in the adjacent one of the resistance wire layers; the isolation member comprising a plurality of insulation disposed between adjacent ones of the resistance wire layers a material layer; the resistance wire portion (81) on the plurality of resistance wire layers are identical in shape and overlap in position. The heating assembly of the inductively coupled plasma etching element according to claim 1, wherein the number M of the resistance wire layers is an even number, and the number of the resistance wire connecting portions (82) is N=M-1, the insulation The number of material layers L = N = M-1. The heating assembly of the inductively coupled plasma etching element of claim 2, wherein the current inlet end (83) of the resistance wire assembly (801) is located in the resistance layer of the first layer, the resistance wire assembly The current outlet end (84) of (801) is located in the resistance layer of the last layer; or the current inlet end (83) of the resistance wire assembly (801) is located in the resistance layer of the last layer, the resistance wire assembly ( The current outlet end (84) of 801) is located in the resistance wire layer of the first layer. The heating assembly of the inductively coupled plasma etching element of claim 3, wherein the heating assembly (8) further comprises the current inlet end (83) connecting the resistance wire assembly (801) and the current outlet Terminal (84) power supply (9). A method of providing a heating assembly in an inductively coupled plasma etched element according to any one of claims 1 to 4, wherein the method comprises layering a complete electrical resistance wire assembly (801) The resistance wire assembly (801) is divided into a resistance wire portion (81) and a resistance wire connection portion (82). The resistance wire portion (81) is stacked on top of each other, and each layer of the resistance wire portion (81) forms a resistance wire layer. The resistance wire connecting portion (82) is connected to at least two of the resistance wire portions (81) located in the adjacent one of the resistance wire layers, and the method further comprises an isolation component, wherein the isolation component comprises a plurality of resistors disposed adjacent to the resistor The insulating material layer between the silk layers; the layered electrical resistance wire assembly (801) satisfies the following conditions: the resistance wire portion (81) on the plurality of resistance wire layers have the same shape and the positions are vertically overlapped, and the resistance wire is The area of the closed loop of assembly (801) is reduced to approach zero. A method of providing a heating assembly in an inductively coupled plasma etching element according to claim 5, wherein the number M of the resistance wire layers is an even number, and the number of the resistance wire connecting portions (82) is N=M-1 The number of the insulating material layers is L = N = M-1. The method of providing a heating assembly in an inductively coupled plasma etching element according to claim 6, wherein the current inlet end (83) of the resistance wire assembly (801) is located in the resistance layer of the first layer, The current outlet end (84) of the resistance wire assembly (801) is located in the resistance layer of the last layer; or the current inlet end (83) of the resistance wire assembly (801) is located on the resistance layer of the last layer, the resistor The current exit end (84) of the wire assembly (801) is located in the resistance wire layer of the first layer. An inductively coupled plasma etching element, the inductively coupled plasma etching element (1) comprising: an induction coil (2), the two ends of the induction coil (2) being connected to a radio frequency source (3) by a lead (201), The induction coil (2) generates an induced magnetic field under the excitation of the RF source (3); the vacuum chamber (101), the reaction gas in the vacuum chamber (101) is generated by the induced magnetic field generated by the induction coil (2). a plasma (102) for etching the semiconductor substrate (5); a ceramic RF window (103) for isolating the induction coil (2) from the vacuum chamber (101); a heating assembly (8), the setting In the inductively coupled plasma etch element, the heating assembly (8) includes a resistance wire assembly (801) and an isolation assembly, the resistance wire assembly (801) and the isolation assembly being disposed on an upper surface of the ceramic RF window (103), Located below the induction coil (2); the resistance wire assembly (801) comprises: a plurality of resistor wire portions (81) arranged one above another, each of the resistance wire portions (81) forming a resistance wire layer; the connection is located adjacent to The resistor At least two resistance wire connecting portions (82) of the resistance wire portion (81) in the layer; the isolation assembly includes a plurality of insulating material layers disposed between adjacent ones of the resistance wire layers; the plurality of resistance wire layers The resistance wire portions (81) are identical in shape and overlap in position. The inductively coupled plasma etching element according to claim 8, wherein the number M of the resistance wire layers is an even number, the number of the resistance wire connecting portions (82) is N = M-1, and the number of the insulating material layers L = N = M-1. The inductively coupled plasma etching element of claim 9, wherein the current inlet end (83) of the resistance wire assembly (801) is located in the resistance layer of the first layer, the resistance wire assembly (801) The current outlet end (84) is located in the last layer of the resistance wire layer; or the current inlet end (83) of the resistance wire assembly (801) is located in the last layer of the resistance wire layer, the resistance wire assembly (801) The current outlet end (84) is located in the resistance layer of the first layer. The inductively coupled plasma etching element of claim 10, wherein the heating assembly (8) further comprises the current inlet end (83) and the current outlet end (84) connected to the resistance wire assembly (801). Power supply (9).