CN116864365A

CN116864365A - Electronic control collimator assembly, substrate processing chamber and process debugging method

Info

Publication number: CN116864365A
Application number: CN202310838044.0A
Authority: CN
Inventors: 潘兴强
Original assignee: Chenwei Equipment Technology Suzhou Co ltd
Current assignee: Chenwei Equipment Technology Suzhou Co ltd
Priority date: 2023-07-10
Filing date: 2023-07-10
Publication date: 2023-10-10

Abstract

The invention discloses an electric control collimator assembly, which comprises a first combined structure formed by combining at least one collimator sheet-shaped unit, wherein the collimator sheet-shaped unit comprises a plurality of through holes penetrating through a first surface and a second surface and a hole wall. The walls of the holes can be connected to a bias. The quasi-collimator leaf cells have a combined function. The first combination structure has a first set of tuning parameters including: the number of sheets of collimator sheet elements, the bias of each collimator sheet element, the configuration of the through-holes of each collimator sheet element and the configuration of the hole walls, the height between the first and second surfaces of each collimator sheet element, the spacing between each of said collimator sheet elements. The invention also discloses a substrate processing chamber and a process debugging method of the substrate processing chamber. The electric control collimator assembly has the advantages of simple structure and easy processing, can improve the debugging performance of different node manufacturing processes, can further improve the ion proportion and straightness, and improves the filling capacity of a small structure.

Description

Electronic control collimator assembly, substrate processing chamber and process debugging method

Technical Field

The present invention relates to semiconductor integrated circuit fabrication equipment, and in particular to an electrically controlled collimator assembly (electric collimator assembly). The invention also relates to a substrate processing chamber. The invention also relates to a process debugging method of the substrate processing chamber.

Background

Physical Vapor Deposition (PVD) often uses collimators (collimators) to increase the duty cycle of the directly deposited particles to achieve increased coverage of the microstructure, particularly the coverage of the bottom of the structure, during filling or coating of the microstructure. The collimator mainly has 2 big effects: (1) And filtering/blocking sedimentary particles with poor straightness, and leading to the duty ratio of the sedimentary particles. (2) Blocking part of neutral deposited particles and increasing ion proportion.

The collimator PVD is mainly applied to the PVD copper Seed layer (PVD Cu Seed) advanced process of the back-end chip below the 40nm technology node. The node further develops a collimator (Biasable Collimator) which can apply bias voltage, namely an electrically controlled collimator (electric collimator), after 10nm, so as to further improve the ion proportion and the straightness, thereby meeting the requirement of smaller line width structure coverage.

The technical requirements of Cu Seed are high bottom coverage of the structure, continuous sidewalls, and avoidance of overhangs (overhangs). In order to achieve the above objectives, the equipment technology focuses on increasing ion density and improving the straightness of copper deposition particles, so that the mainstream technology adopts increasing power and increasing magnetic field strength to increase ion density, lengthen the distance from the target to the wafer, and apply rf bias to the substrate carrying the wafer to enhance ion straightness, wherein the substrate is a wafer bottom seat, and an electrostatic chuck (ESC) is generally used. However, as technology nodes iterate, the line width of the back-end wire is greatly reduced, so that almost every generation of technology index needs to be filled with new copper Seed layer (Cu Seed) equipment, the main stream technology from 40nm cannot cope with the requirement of covering the structural film, a Collimator (Collimator) must be used to meet the requirement of covering the structural film, the industry also names the Collimator as Flux Optimizer (FO), and 40,28,20,14nm each generation has a modified version of the Collimator structure. The later line width is reduced to below 20nm when reaching the 10nm process node, and meanwhile, the process requirement of Cu Seed is more clear, so that the bottom coverage rate of the structure is further improved, and a direct current bias voltage is required to be applied on the traditional collimator, thereby further improving the ion density and the straightness.

The PVD Cu Seed at the process node of 40-14nm has the defects that the collimator is a single piece, thick, complex in shape and high in cost, each generation has different versions, and if the PVD Cu Seed needs to be debugged, the PVD Cu Seed can only be manufactured by re-opening the die, cannot be shared, and the mutual support of equipment is low.

The 10nm process node post collimator uses the bias collimator disclosed in US 11309169 B2, which is also a conventional collimator as described above but is biased, but only with one bias. And the initial research and development has found that the shape of the collimator is transferred onto the wafer due to excellent straightness, which is called a Printing effect (Printing effect), and the transfer effect needs to be eliminated while improving the straightness of the collimator.

Disclosure of Invention

The invention aims to solve the technical problem of providing an electric control collimator assembly, which has the advantages of simple structure and easy processing, can improve the debugging performance of different node processes, can further improve the ion proportion and straightness, and improves the filling capacity of a small structure. To this end, the invention also provides a substrate processing chamber. The invention also provides a process debugging method of the substrate processing chamber.

In order to solve the technical problems, the invention provides an electric control collimator assembly, which comprises a first combined structure formed by combining at least one collimator sheet-shaped unit.

The collimator sheet unit has a first surface and an opposite second surface, a plurality of through holes penetrating the first surface and the second surface, and a hole wall surrounding the through holes.

The aperture wall of the collimator pellet has electrical conductivity and is connectable to a bias voltage.

The lamellar structure of the collimator lamellar unit gives the collimator lamellar unit a combined function.

The electrically controlled collimator assembly comprises a first combined structure formed by combining a plurality of collimator sheet units.

The first combination structure is provided with a first adjusting parameter set for realizing process adjustment.

The parameters of the first set of adjustment parameters include: the number of sheets of said collimator sheet elements, the bias of each said collimator sheet element, the configuration of said through-holes of each said collimator sheet element and the configuration of said hole walls, the height between the first and second surfaces of each said collimator sheet element, the spacing between each said collimator sheet element; the values of the parameters of the first set of adjustment parameters are determined by the process and meet the requirements of the working process.

A further improvement is that the height between the first surface and the second surface of each collimator sheet-like element is 0.5cm to 15cm.

The collimator sheet unit has the number of sheets of 1 sheet, 2 sheets or more than 3 sheets.

A further improvement is that the spacing between the collimator sheet-like units is 0.1cm to 20cm.

A further improvement is that the bias voltage of each collimator pellet is provided by an independent bias voltage power supply which provides either a dc bias voltage or an ac bias voltage.

A further improvement is that the constituent material of the hole wall of each collimator sheet-like unit includes a conductive material or an insulating material coated with a conductive film on the surface.

A further improvement is that the cross-sectional shape of the through-hole of the collimator sheet-like unit comprises a circle or a polygon.

A further improvement is that the distribution structure of the through holes on the collimator sheet-like unit in cross section comprises:

the cross-sectional shape of the through holes in each region of the collimator sheet-like unit is the same, and the cross-sectional area is the same.

Alternatively, the cross-sectional area of the through-hole of each region of the collimator sheet-like unit has a first variation structure.

The first variation includes:

the cross-sectional area of the through hole becomes either a first progressively larger or a first regional larger in a first direction from the center to the outer edge of the collimator sheet-like element.

The first progressive enlargement means that the cross-sectional area of each of the through holes increases in sequence.

The first area becoming larger means that the cross-sectional area of the through holes increases sequentially according to first areas, each of the first areas including one or more adjacent through holes and at least one of the first areas including two or more adjacent through holes.

In a further development, the collimator sheet-like element is circular in plan view, and the cross-sectional shape and the cross-sectional area of the respective through-holes are identical or different in one annular region of the collimator sheet-like element.

In a further improvement, the collimator sheet-shaped unit is circular in a top view, and the through holes are symmetrically distributed or asymmetrically distributed along the circle center of the collimator sheet-shaped unit.

A further improvement is that the height of each region of the collimator pellet is equal; alternatively, the height of each region of the collimator sheet-like element has a second variation.

The second variation includes:

the height of the individual areas of the collimator sheet element becomes lower in a second progressive or second regional direction from the centre to the outer edge of the collimator sheet element.

The second progressive lowering means that the height of each hole wall becomes lower in sequence.

The second area becomes lower means that the height of the hole wall becomes lower in sequence according to the second areas, each second area comprises more than one adjacent hole wall, and at least one second area comprises more than two adjacent hole walls.

In a further improvement, the aspect ratio of the through holes on the collimator sheet units or between the collimator sheet units is the same or different, the shapes of the through holes are the same or different, and the sizes of the through holes are the same or different.

The number of the through holes between the collimator sheet units is the same or different.

In a further improvement, in the first combined structure, the areas surrounded by the outer edges of the collimator sheet-shaped units are the same in size, and the collimator sheet-shaped units are arranged in parallel and aligned in the center.

Further improvements include PVD processes with process nodes of 40nm, 28nm, 14nm, 7nm and below 5 nm.

In a further improvement, the dc bias voltage provided by the bias voltage power supply includes a positive bias voltage, a negative bias voltage and a 0 bias voltage, the magnitude of the positive bias voltage is adjustable, the magnitude of the negative bias voltage is adjustable, and the waveform and frequency of the ac bias voltage provided by the bias voltage power supply are adjustable.

The bias voltage of each collimator sheet unit is selected or switched between the positive bias voltages of different magnitudes, the negative bias voltages of different magnitudes, the 0 bias voltage and the alternating bias voltages of different waveforms and frequencies according to process requirements.

In the first combined structure, the bias voltage of each collimator sheet unit is independently set; when more than 2 collimator sheet units are arranged in the first combined structure, the electric field type collimation structure is formed by combining the bias voltages of all the collimator sheet units.

A mounting part is arranged at the peripheral edge position of the collimator sheet-shaped unit, and the mounting part is of a conductive structure; the mounting part is used for realizing detachable fixed mounting and electric connection of the collimator sheet unit.

In order to solve the above technical problems, the substrate processing chamber provided by the present invention includes: a target material and a wafer base which are placed in the reaction cavity; an electrically controlled collimator assembly is also included.

The electrically controlled collimator assembly comprises a first combined structure formed by combining at least one collimator sheet-shaped unit;

The first combined structure is arranged inside the reaction cavity and is positioned between the target and the wafer bottom seat.

The wafer base is a rotary wafer base and is used for rotating in the process to eliminate the transfer effect (printing effect); the through holes of the collimator sheet units are asymmetrically arranged.

Further improvement is that the structure for fixing the wafer by the wafer base comprises: an electrostatic chuck or a vacuum chuck.

In order to solve the above technical problems, the process debugging method for a substrate processing chamber provided by the present invention comprises the following steps:

step one, manufacturing a plurality of collimator sheet units.

Each collimator sheet unit has a first surface and an opposite second surface, a plurality of through holes penetrating the first surface and the second surface, and a hole wall surrounding the through holes.

And step two, forming an electric control collimator assembly, wherein the electric control collimator assembly comprises a first combined structure formed by combining a plurality of collimator sheet units.

The first combination structure has a first set of adjustment parameters, the parameters of the first set of adjustment parameters including: the number of sheets of the collimator sheet-like elements, the bias of each of the collimator sheet-like elements, the structure of the through-hole of each of the collimator sheet-like elements and the structure of the hole wall, the height between the first surface and the second surface of each of the collimator sheet-like elements, the spacing between each of the collimator sheet-like elements.

And step three, performing process debugging, wherein in the process debugging process, the values of the corresponding parameters in the first adjusting parameter set are continuously changed until the requirements of the process are met.

In a further improvement, in the third step, the process includes a PVD process.

In the third step, in the first combined structure, the bias voltages of the collimator sheet units are independently arranged, and when more than 2 collimator sheet units are arranged in the first combined structure, an electric field type collimation structure is formed by combining the bias voltages of all the collimator sheet units; the electric field type collimation structure realizes electric field focusing and ion acceleration on the deposited particles in the PVD process, and improves the straightness of the deposited particles.

A further improvement is that the deposition particles of the PVD process comprise positive ion particles.

When the bias of the collimator sheet unit is negative, the collimator sheet unit will exert an attracting effect on the positive ion particles.

When the bias of the collimator sheet unit is positive, the collimator sheet unit will exert a bias collimation action or an acceleration exit action on the positive ion particles.

Compared with the existing collimator adopting a complex-shape single body, the thickness of the collimator sheet unit is thinner, such as 0.5 cm-15 cm, so that the collimator sheet unit has the advantages of simple structure, easy processing and low manufacturing cost.

The existing single collimator with complex shape is thicker, occupies larger space and cannot realize the combination of a plurality of single collimators, and the collimator sheet-shaped unit can also realize the combination of a plurality of sheets so as to form a first combined structure; the first combination structure has a first adjustment parameter set, which makes the first combination structure convenient to adjust, in particular to adjust according to the requirements of the process, and can improve the debugging performance of different node processes, for example: the process requirements of different process nodes can be met in the same PVD equipment, namely, the application nodes can be switched by changing and increasing and decreasing the sheets, namely the collimator sheet units, only by using the time of one-time equipment maintenance (PM), and the same PVD equipment can be applied to 40nm to 5nm advanced processes without a model; for example, when switching from a 40nm process node to a 28nm process node, the PVD equipment in the prior art needs to be replaced, which requires a large cost; the invention can be realized only by carrying out parameter adjustment on the first combined structure.

Compared with the existing single collimator with complex shape, the bias voltage of each collimator sheet unit in the first combined structure can be independently set, when more than 2 collimator sheet units are arranged in the first combined structure, an electric field type collimation structure can be formed through the bias voltage combination of all the collimator sheet units, so that the ion proportion and the straightness can be further improved, the coverage rate (bottom coverage) of a bottom structure is greatly improved, and the filling capacity of a small structure is improved. The existing single collimator with complex shape cannot form the electric field type collimation effect formed by the bias combination, and the existing method needs to make complex design on the shape of the single collimator in order to improve the collimation effect, namely the ion proportion and the straightness, which obviously limits the improvement of the collimation effect; the collimation effect can be improved by adjusting the parameters of the first adjustment parameter set of the first combination structure, for example, by adjusting the offset combination formed by each bias voltage, so that the invention can realize filling of smaller structures such as grooves, and is more suitable for application in advanced processes, such as bottom-up fill (bottom-up fill) or PVD processes requiring bottom coverage, for example, the back-end PVD copper Seed layer (Cu Seed).

Because the transfer printing effect is easy to occur when the straightness of the collimator is good, the transfer printing effect can be eliminated by combining the distribution of the asymmetric or non-single through holes of the rotary wafer base and the collimator sheet unit, so that the deposition quality can be improved.

Drawings

The invention is described in further detail below with reference to the attached drawings and detailed description:

FIG. 1 is a schematic diagram of an electrically controlled collimator assembly according to an embodiment of the invention;

FIGS. 2A-2E are top plan view block diagrams of 5 collimator sheet elements in an electrically controlled collimator assembly according to an embodiment of the invention;

FIGS. 3A-3B are cross-sectional block diagrams of 2 collimator sheet elements in an electrically controlled collimator assembly according to an embodiment of the invention;

FIG. 4 is a schematic view of a substrate processing chamber according to an embodiment of the present invention;

FIG. 5 is a schematic view of a substrate processing chamber according to a preferred embodiment of the invention;

fig. 5A is a schematic diagram of a top plan view of the collimator sheet-like unit added to that of fig. 5.

Detailed Description

FIG. 1 is a schematic diagram of an electrically controlled collimator assembly according to an embodiment of the present invention; an electrically controlled collimator assembly according to an embodiment of the invention comprises a first combination structure 101 formed by combining at least one of said collimator lamellae units.

The collimator sheet unit has a first surface and an opposite second surface, a plurality of through holes 103 penetrating the first surface and the second surface, and a hole wall 104 surrounding the through holes 103. In fig. 1, 3 sheets of said collimator sheet-like units are shown, indicated with the marks 102a, 102b and 102c, respectively.

The aperture wall 104 of the collimator pellet has electrical conductivity and is connectable to a bias voltage.

The first combination structure 101 has a first adjustment parameter set for realizing process adjustment.

The parameters of the first set of adjustment parameters include: the number of sheets of the collimator sheet-like elements, the bias of each of the collimator sheet-like elements, the structure of the through-hole 103 and the structure of the hole wall 104 of each of the collimator sheet-like elements, the height between the first surface and the second surface of each of the collimator sheet-like elements, the spacing between each of the collimator sheet-like elements; the values of the parameters of the first set of adjustment parameters are determined by the process and meet the requirements of the working process. That is, in the embodiment of the present application, the values of the parameters of the first adjustment parameter set have the characteristic of adjustability, and the adjustment is completely performed according to the needs of the process, when the process changes, the values of the parameters of the first adjustment parameter set can be correspondingly changed, so that the first combined structure 101 is finally re-applied to the changed process, that is, the needs of the process can be satisfied. Therefore, in the embodiment of the present application, the values of the parameters of the first adjustment parameter set are finally determined by the process, that is, the values of the parameters of the first adjustment parameter set can be obtained under the condition of definite process, so that the specific structure of the first combined structure 101 can be obtained; the method for obtaining the values of the parameters of the first adjustment parameter set from the process may refer to a process tuning method for a substrate processing chamber according to an embodiment of the present application described later in the specification.

In some embodiments, the height between the first surface and the second surface of each of the collimator sheet elements is 0.5cm to 15cm; in some preferred embodiments, the height between the first surface and the second surface of each of the collimator sheet-like units can be taken as 1cm, 2cm, 3cm, 4cm, 5cm, 6cm, 7cm, 8cm, 9cm, 10cm, 11cm, 12cm, 13cm, 14cm, etc. The smaller height makes each of the collimator sheet-like units simple in structure and easy to machine.

In some embodiments, the collimator sheet unit has a number of sheets of 1, 2, or 3 or more, for example, 4, 5, 6, 7, or the like. In fig. 1, the collimator sheet unit is shown as 3 sheets. As described above, the specific number of collimator sheet units required in the first combination structure 101 is set entirely by the specific process, and in the embodiment of the present invention, the number of collimator sheet units is convenient to implement. However, the existing monolithic collimator cannot be assembled due to its own structure, and the first assembled structure 101 with adjustable parameters in the embodiment of the present invention cannot be realized.

In the embodiment of the invention, the process comprises PVD processes with process nodes of 40nm, 28nm, 14nm, 7nm and below 5 nm.

In some embodiments, the spacing between each of the collimator pellets is from 0.1cm to 20cm. In some preferred embodiments, the spacing between the collimator sheet elements can be 0.5cm, 1cm, 1.5cm, 2cm, 3cm, 4cm, 5cm, 6cm, 7cm, 8cm, 9cm, 10cm, 11cm, 12cm, 13cm, 14cm, 15cm, 16cm, 17cm, 18cm, 19cm, etc.; the method can also be as follows: the spacing between the collimator pellets is adjusted to an accuracy of 0.1cm or other dimensions, for example, when the current spacing is 5cm, then an increase of 0.1cm per increase or a decrease of 0.1cm per decrease can be used.

In the embodiment of the invention, the mounting part 105 is arranged at the peripheral edge position of the collimator sheet unit, and the mounting part 105 is of a conductive structure; the mounting portion 105 is used for detachably fixing and electrically connecting the collimator sheet-like unit.

In an embodiment of the present invention, the bias voltage of each collimator sheet unit is provided by an independent bias power supply, and the bias power supply provides a dc bias voltage or an ac bias voltage. As shown in fig. 1, 3 of the bias power supplies, labeled 106a, 106b, and 106c, respectively, are used to bias the collimator sheet units 102a, 102b, and 102c, respectively. In some embodiments, the bias power supply can be included as part of the electrically controlled collimator assembly, i.e., the electrically controlled collimator assembly is formed from each of the bias power supplies and the first combination 101 together. In other embodiments the bias power supply can be provided externally, i.e. it is not itself an integral part of the electrically controlled collimator assembly, but only in use it is provided to provide the required bias voltage to each of the collimator leaves of the electrically controlled collimator assembly.

In the embodiment of the present invention, the dc bias voltage provided by each bias voltage power supply includes a positive bias voltage, a negative bias voltage and a 0 bias voltage, the magnitude of the positive bias voltage is adjustable, the magnitude of the negative bias voltage is adjustable, and the waveform and frequency of the ac bias voltage provided by the bias voltage power supply are adjustable.

The bias voltage of each collimator sheet unit is selected or switched between the positive bias voltages of different magnitudes, the negative bias voltages of different magnitudes, the 0 bias voltage and the alternating bias voltages of different waveforms and frequencies according to process requirements. That is, for example, the same collimator sheet unit may be applied with the positive bias voltage or the negative bias voltage, and may be applied with the positive bias voltage when the collimator sheet unit needs to be fixed with the positive bias voltage, and with the negative bias voltage when the collimator sheet unit needs to be fixed with the negative bias voltage, and may be applied with the bias voltage switching if the collimator sheet unit needs to be switched.

As can be seen from fig. 1, in the first combination structure 101, the bias voltages of the collimator sheet units are independently set; when there are more than 2 collimator leaves in the first combined structure 101, an electric field type collimation structure is formed by the combination of the bias voltages of all the collimator leaves. In the embodiment of the invention, the electric field type collimation structure is completely obtained through the combination of bias voltages, and the principle of realizing particle collimation through the shape structure of the through holes is different from the existing principle that the particle collimation is realized through the shape structure of the through holes, wherein the through holes are utilized to mechanically block particles in some directions and particles in other directions; the electric field type collimation structure utilizes bias voltage setting of the collimator sheet units at different positions to form electric fields which are favorable for collimation of charged particles at different positions, and the straightness and ion proportion of the charged particles are increased after the charged particles pass through the electric fields, namely the collimation effect is increased.

In the embodiment of the present application, the constituent material of the hole wall 104 of each collimator sheet unit includes a conductive material or an insulating material coated with a conductive film on the surface. In some embodiments, the constituent materials of the hole walls 104 of each of the collimator sheet units can be all conductive materials or all insulating materials with conductive films coated on the surfaces. In other embodiments, the hole wall 104 of each collimator sheet unit may be made of a conductive material, and the other remaining portions may be made of an insulating material coated with a conductive film.

The cross-sectional shape of the through-hole 103 of the collimator sheet-like unit includes a circle or a polygon, for example, a hexagon, a triangle, a quadrangle, a pentagon, an octagon, or the like, and the cross-section of the through-hole 103, i.e., the structure on the plane view can be a symmetrical structure or an asymmetrical structure. In the present application, the cross section of the through-hole 103 is a plane perpendicular to the extending direction of the through-hole 103, and the plane corresponding to fig. 2A to 2E is the cross section of the through-hole 103.

The distribution structure of the through holes 103 in the collimator sheet unit in cross section includes:

in some embodiments, the cross-sectional shape and cross-sectional area of the through holes 103 of each region of the collimator sheet unit are the same.

In some embodiments can also be: the cross-sectional area of the through-hole 103 of each region of the collimator sheet-like unit has a first variation. The first variation includes:

the cross-sectional area of the through-hole 103 becomes either a first progressively larger or a first regional size in a first direction from the center to the outer edge of the collimator sheet-like element.

The first progressive enlargement means that the cross-sectional area of each of the through holes 103 increases in sequence.

The first areas becoming larger means that the cross-sectional area of the through-holes 103 increases sequentially according to first areas, each of which includes one or more adjacent through-holes 103 and at least one of which includes two or more adjacent through-holes 103.

In an embodiment of the present invention, the collimator sheet unit is circular in a top view.

In some embodiments, the cross-sectional shape and cross-sectional area of each of the through holes 103 are the same or different and the cross-sectional area is the same or different over one annular region of the collimator sheet unit.

In some embodiments, each of the through holes 103 is symmetrically or asymmetrically distributed along the center of the collimator sheet unit. In some preferred embodiments, the center position of the through hole 103 located in the center region of the collimator sheet unit and the center position of the collimator sheet unit are not aligned, but have an offset, for example: for a selected one of the through holes 103 located in the central region of the collimator sheet-like element, the spacing between the center of the collimator sheet-like element and any one of the edges of the selected through hole 103 is 1% -49% of the spacing between the center position and the edge of the selected through hole 103.

In some embodiments, the height of the regions of the collimator pellet is equal.

In some embodiments can also be: the height of each region of the collimator pellet has a second variation.

The second variation includes:

The second progressive increase means that the height of each of the hole walls 104 becomes lower in sequence. The second progressive lowering is shown in fig. 3A, fig. 3A shows the collimator sheet-like element corresponding to the mark 102f, it can be seen that the height of each area of the collimator sheet-like element is mainly determined by the height of the hole wall 104 of each area, and it can be seen that the height of the hole wall 104 gradually decreases in the first direction

The second area becoming lower means that the height of the hole wall 104 becomes lower in sequence according to second areas, each of the second areas includes more than one adjacent hole wall 104 and at least one of the second areas includes more than two adjacent hole walls 104. As shown in fig. 3B, where the second area becomes lower, the collimator sheet-like unit corresponding to the mark 102g is shown in fig. 3B, and it can be seen that 3 areas corresponding to the marks 107a, 107B and 107c are shown in the first direction corresponding to one radius, where the area 107a actually has only one hole wall 104, where the areas 107B and 107c have 2 hole walls 104 respectively, where the heights of the hole walls 104 in the same area are equal, and where the heights of the hole walls 104 in adjacent areas sequentially change, for example, the heights of 2 hole walls 104 in the area 107B are equal, and where the heights of 2 hole walls 104 in the area 107c are equal, but where the heights of 2 hole walls 104 in the area 107B in the area 107c are smaller than the heights of 2 hole walls 104 in the area 107B.

In the embodiment of the present invention, the aspect ratio of each through hole 103 on each collimator sheet unit or between each collimator sheet units is the same or different, the shape of each through hole 103 is the same or different, and the size of each through hole 103 is the same or different. The aspect ratio of the through-hole 103 is a ratio of the depth to the width of the through-hole 103, and the aspect ratio of the through-hole 103 can be achieved by adjusting the cross-sectional area of the through-hole 103 and the height of the hole wall 104 described above.

The number of through holes 103 between the collimator sheet units is the same or different.

In the first combination structure 101, the area surrounded by the outer edges of the collimator sheet units is the same, and the collimator sheet units are arranged in parallel and aligned in the center. In other embodiments, it can also be: the size of the area surrounded by the outer edges of the collimator sheet units is different, a certain angle is formed between the collimator sheet units, a certain offset is formed in the center position, and the specific size, arrangement and alignment mode of the area surrounded by the outer edges of the collimator sheet units can be adjusted according to actual needs.

In some preferred embodiments, since the straightness achieved by the first combined structure 101 is better, in order to prevent the transfer effect, that is, the pattern of the through holes 103 in the first combined structure 101 is transferred to the substrate, the through holes 103 of each collimator sheet unit are arranged asymmetrically.

For a clearer illustration of the electrically controlled collimator assembly according to an embodiment of the present invention, fig. 2A to 2E show top view block diagrams of 5 collimator sheet units in the electrically controlled collimator assembly according to an embodiment of the present invention, and 5 collimator sheet units are denoted by reference numerals 102A, 102b, 102C, 102d and 102E, respectively, and 3 collimator sheet units shown in fig. 2A to 2C are applied to the collimator assembly structure 101 shown in fig. 1 and are stacked together in sequence. In fig. 2A to 2E, the outermost hole wall 104 of each collimator sheet unit has a circular shape, and the mounting portion 105 is fixedly disposed on the outer surface of the outermost hole wall 104 of the collimator sheet unit, for example: the mounting portion 105 can be integrally formed on the outer side surface of the hole wall 104 on the outermost side of the collimator sheet unit so as to realize the fixed arrangement of the mounting portion 105; the mounting portion 105 may be fixedly disposed on the outer surface of the outermost hole wall 104 of the collimator sheet-like unit by welding or screws or other fixing means. Each of the through holes 103 is formed by dividing the hole wall 104 into a plurality of straight lines, so that the through holes are in a rectangular structure; the hole wall 104 is formed such that one side of each through hole 103 outside each through hole 103 is the outermost side.

As can be seen from the sectional structure of fig. 1, the top width of each hole wall 104 is reduced and inclined sides are formed in the top region where the width is gradually reduced, the top opening of the through hole 103 is enlarged, which prevents the through hole 103 from being blocked, and the inclined sides further prevent particles deposited on the sides of the hole wall 104 from being detached and causing particle contamination.

Fig. 1 and fig. 2 only show an example of a collimator assembly structure 101 according to an embodiment of the present invention, the structure of each collimator sheet unit can be adjusted according to actual needs, for example, the structure of the top surface of the through hole 103 can also be polygonal or circular, and the structure of the top surface of the through hole 103 can be a symmetrical structure or an asymmetrical structure, for example, a hexagon, a triangle, a quadrilateral, a pentagon, an octagon, etc.; in some embodiments, the stacking order of the collimator sheet units of the collimator assembly structure 101 shown in fig. 1 can be adjusted, and the type and number of the collimator sheet units used in the collimator assembly structure 101 shown in fig. 1 can also be adjusted according to the needs, which is not specifically described in the present specification.

Compared with the existing collimator adopting a complex-shape single body, the collimator sheet unit has the advantages of thinner thickness of 0.5 cm-15 cm, simple structure, easy processing and low manufacturing cost.

The existing single collimator with complex shape is thicker, occupies larger space and cannot realize the combination of a plurality of single collimators, but the collimator sheet-shaped unit of the embodiment of the invention can also realize the combination of a plurality of sheets so as to form a first combined structure 101; the first combination structure 101 has a first adjustment parameter set, which makes the first combination structure 101 convenient to adjust, especially makes it convenient to adjust according to the requirements of the process, and can improve the debugging performance of different node processes, for example: the process requirements of different process nodes can be met in the same PVD equipment, namely, the application nodes can be switched by changing and increasing and decreasing the sheets, namely the collimator sheet units, only by using the time of one-time equipment maintenance (PM), and the same PVD equipment can be applied to 40nm to 5nm advanced processes without a model; for example, when switching from a 40nm process node to a 28nm process node, the PVD equipment in the prior art needs to be replaced, which requires a large cost; the embodiment of the present invention can be implemented by only performing parameter adjustment on the first combined structure 101.

Compared with the existing single collimator with complex shape, only one bias voltage can be added, the bias voltages of all collimator sheet units in the first combined structure 101 can be independently set, when the first combined structure 101 is provided with more than 2 collimator sheet units, an electric field type collimation structure can be formed by combining the bias voltages of all collimator sheet units, so that the ion proportion and the straightness can be further improved, the coverage rate (bottom coverage) of a bottom structure is greatly improved, and the filling capacity of a small structure is improved. The existing single collimator with complex shape cannot form the electric field type collimation effect formed by the bias combination, and the existing method needs to make complex design on the shape of the single collimator in order to improve the collimation effect, namely the ion proportion and the straightness, which obviously limits the improvement of the collimation effect; the collimation effect can be improved by adjusting the parameters of the first adjustment parameter set of the first combination structure, for example, by adjusting the offset combination formed by each bias voltage, so that the embodiment of the invention can realize filling of smaller structures such as grooves, and is more suitable for application in a first process, such as a bottom-up fill (bottom-up fill) or PVD (bottom coverage) process, for example, a subsequent PVD copper Seed layer (Cu Seed).

Because the transfer effect is easy to occur when the straightness of the collimator is better, the transfer effect can be eliminated by combining the distribution of the asymmetric or non-single through holes 103 of the rotary wafer base 203 and the collimator sheet unit, so that the deposition quality can be improved.

FIG. 4 is a schematic view of a substrate processing chamber according to an embodiment of the present invention; the substrate processing chamber according to the embodiment of the invention comprises:

a target 202 and a wafer pedestal 203 disposed inside the reaction chamber; the interior of the reaction chamber is an interior space formed by the chamber wall 201. A wafer 204 is placed on the wafer pedestal 203.

An electrically controlled collimator assembly is also included.

the collimator sheet unit has a first surface and an opposite second surface, a plurality of through holes 103 penetrating the first surface and the second surface, and a hole wall 104 surrounding the through holes 103. In fig. 4, 3 of the collimator pellets shown at 102a, 102b and 102c are listed.

The electrically controlled collimator assembly comprises a first combination structure 101 formed by combining a plurality of collimator sheet-like units.

The first combined structure 101 is disposed inside the reaction chamber and between the target 202 and the wafer pedestal 203.

The parameters of the first set of adjustment parameters include: the number of sheets of the collimator sheet-like elements, the bias of each of the collimator sheet-like elements, the structure of the through-hole 103 and the structure of the hole wall 104 of each of the collimator sheet-like elements, the height between the first surface and the second surface of each of the collimator sheet-like elements, the spacing between each of the collimator sheet-like elements.

The wafer pedestal 203 is a rotary wafer pedestal 203, and is configured to rotate during a process to eliminate a transfer effect, and a dotted line indicated by 205 indicates that the wafer pedestal 203 has a rotation function. The wafer fixing structure of the wafer base 203 includes: an electrostatic chuck or a vacuum chuck.

To further eliminate the transfer effect, the through holes 103 of each collimator sheet unit are arranged asymmetrically.

In fig. 4, the details of the electrically controlled collimator assembly are referred to the previous description of the electrically controlled collimator assembly according to an embodiment of the invention alone, and will not be described herein.

The electrically controlled collimator assembly of the present invention may be applied to various types of substrate processing chambers, and only the structures associated with understanding the substrate processing chamber of the present invention are shown in fig. 4. In practice, the substrate processing chamber further comprises: and the vacuum system is used for vacuumizing the inner space of the substrate processing chamber. A gas line for providing a process gas to an interior space of the substrate processing chamber. Some of the substrate processing chambers further include a magnetron for forming a plasma at a bottom surface area of the target 202 exposed to an interior space of the substrate processing chamber. These structures can be understood by reference to the structure of the existing substrate processing chamber.

For a clearer understanding of the substrate processing chamber according to the embodiment of the present invention, the substrate processing chamber according to the embodiment of the present invention will be further described with reference to a schematic structural diagram of the substrate processing chamber according to the preferred embodiment of the present invention shown in fig. 5:

as shown in fig. 5, the substrate processing chamber according to the preferred embodiment of the present invention comprises:

Chamber walls 201 surround the reaction chamber formed.

The target 202 is arranged on the top of the reaction chamber;

the wafer pedestal 203 is disposed at the bottom of the reaction chamber; a wafer 204 is placed on the wafer pedestal 203.

And also includes an electrically controlled collimator assembly that is identical in construction to that shown in fig. 4 and will not be described in detail herein.

In fig. 5, further includes:

the chamber protection component 301 is configured to protect the reaction chamber, i.e. the inner surface of the chamber wall 201, from contamination and be recycled.

A deposition ring and shadow ring 302 for protecting the substrate tray and the bottom of the reaction chamber from contamination by sputter coated particles.

The magnetic control source 303 is formed by magnetic column groups, and is used for forming a magnetic field by the magnetic column groups arranged according to a certain layout.

The magnetic control source rotating assembly 304, the magnet rotating assembly of the magnetic control source rotating assembly 304 drives the magnet, namely the magnetic column of the magnetic control source 303, to rotate, and the magnetic field rotates along with the rotating path of the magnet so as to drive the plasma to move to realize bombardment of different areas of the target 202.

The dc power supply 305 is configured to provide high-voltage high-energy dc power to the target 202, and ionize the high-purity gas in the reaction chamber under the magnetic field of the magnet behind the target 202 to form plasma.

A bias power supply 306 for providing the bias voltages 106a, 106b and 106c of each of the collimator pellets described above.

A rf bias power supply 307 is applied to the wafer pedestal 303 to provide a bias voltage to the wafer pedestal 303.

The ring magnet 308 provides a magnetic field and uses the magnetic field to influence and control the movement of charged particles to improve directivity and uniformity.

The vacuum pump interface 309 is used for being connected with a vacuum pump, and maintaining the ultra-high vacuum degree in the reaction chamber by the vacuum pump to maintain the high-purity coating film.

As shown in fig. 5A, which is a schematic structural diagram of a top view of the collimator sheet-like unit added to fig. 5, in fig. 5A, top views of the collimator sheet-like units 102A, 102B and 102C are also shown, and for a more clear enlarged structure of these top views, please refer to fig. 2A, 2B and 2C.

The process debugging method of the substrate processing chamber comprises the following steps:

step one, manufacturing a plurality of collimator sheet units.

Each of the collimator sheet units has a first surface and an opposite second surface, a plurality of through holes 103 penetrating the first surface and the second surface, and a hole wall 104 surrounding the through holes 103.

In the method of the embodiment of the present invention, the types and the number of the prepared collimator sheet units are greater than those required by the specific first combined structure 101 formed later, so as to be selected in the process debugging process.

And step two, forming an electric control collimator assembly, wherein the electric control collimator assembly comprises a first combined structure 101 formed by combining a plurality of collimator sheet-shaped units.

The first combination structure 101 has a first adjustment parameter set, and the parameters of the first adjustment parameter set include: the number of sheets of the collimator sheet-like elements, the bias of each of the collimator sheet-like elements, the structure of the through-hole 103 and the structure of the hole wall 104 of each of the collimator sheet-like elements, the height between the first surface and the second surface of each of the collimator sheet-like elements, the spacing between each of the collimator sheet-like elements.

If the stage equipment of the substrate processing chamber has a sufficient number of bias power supplies, the existing bias power supplies of the stage equipment are directly used for providing bias voltage for each collimator sheet-shaped unit; if the number of bias power supplies on the equipment of the substrate processing chamber is insufficient, the corresponding bias power supplies are added.

In the method of the embodiment of the invention, the process comprises a PVD process.

In the third step, in the first combination structure 101, bias voltages of the collimator sheet units are independently set, and when more than 2 collimator sheet units are provided in the first combination structure 101, an electric field type collimation structure is formed by combining bias voltages of all the collimator sheet units; the electric field type collimation structure realizes electric field focusing and ion acceleration on the deposited particles in the PVD process, and improves the straightness of the deposited particles.

The deposition particles of the PVD process include positive ion particles.

The combination of the bias voltages of the collimator flaps to form an electric field type collimating structure will now be further described in connection with applying various different bias voltages to each of the collimator flaps of the substrate processing chamber shown in fig. 4, for example:

1. The collimator tab 102a applies a negative bias, the collimator tab 102b applies no bias or a positive bias, and the collimator tab 102c applies a positive bias;

the effects on particle motion are respectively:

attracting positive ions- > biasing collimated positive ions- > accelerates away from the collimator, i.e.:

the collimator sheet-like unit 102a to which a negative bias is applied attracts positive ions, which are sputtered particles; the unbiased or positively biased collimator leaf cell 102b biases collimated positive ions; the collimator sheet element 102c, being positively biased, accelerates ions away from the collimator.

2. The collimator tab 102a applies a positive bias, the collimator tab 102b applies no positive or negative bias, and the collimator tab 102c applies a negative bias;

the effects on particle motion are respectively:

the bias collimates the positive ions— attracting the positive ions.

3. The collimator tab 102a applies a positive bias, the collimator tab 102b applies a negative bias, and the collimator tab 102c applies a positive bias;

the effects on particle motion are respectively:

biasing collimated positive ions- > attracting positive ions- > biasing collimated- > accelerating out of the collimator.

And in the existing single-piece collimator, if the single-piece collimator needs to be debugged, only the mold can be opened again for manufacturing, and when the existing single-piece collimator has an electric control function, only one bias voltage can be applied; the embodiment of the invention can firstly manufacture a plurality of different collimator sheet units (the number of holes, the size, the shape and the aspect ratio …), and then make appropriate combination of various desired numbers according to the process requirement so as to meet the process requirement. Because each slice is independent, the bias voltage can be applied to each slice, and the better collimation debugging requirement can be achieved.

The embodiment of the invention is mainly used in PVD processes requiring bottom-up filling (bottom-up filling) or requiring bottom coverage (bottom coverage), such as back-end Cu Seed.

The embodiment of the invention is characterized in that the collimator combined in multiple parts is used, and the customized adjustment can be carried out according to the requirements of different nodes (28, 14,7,5nm or more) by matching different combinations.

Meanwhile, the bias voltage design with multiple and staggered polarities has the similar focusing and ion acceleration capability, and can effectively improve the straightness of the plated ions, thereby greatly improving the bottom coverage rate of the structure.

However, due to the excellent straightness, the shape transfer phenomenon of the collimator can be generated during film coating, and the embodiment of the invention can simultaneously eliminate the transfer effect by using a rotatable wafer bearing base or combining an asymmetric collimator through hole arrangement mode.

In addition, the embodiment of the invention adopts a thin (0.5-15 cm) collimator, namely a collimator sheet unit, has simple structure and easy processing, and can reduce the expensive manufacturing cost of the original complex-shape single collimator.

The thin collimator combination with different aperture shapes separated from each other is utilized, the processing requirements of different process nodes can be met in the same PVD equipment, namely, the application nodes can be switched by changing and increasing and decreasing the thin sheets only by using the time of one-time equipment maintenance (PM), and the same equipment can be applied to the advanced processing of 40nm to 5nm without a model.

Each piece of the combined collimator, namely the electric control collimator assembly, can be independently biased, and the electric field type collimation effect can be formed by the simple structure of the collimator but by using the bias combination, so that the single collimator with complex shape is replaced.

The present invention has been described in detail by way of specific examples, but these should not be construed as limiting the invention. Many variations and modifications may be made by one skilled in the art without departing from the principles of the invention, which is also considered to be within the scope of the invention.

Claims

1. An electrically controlled collimator assembly comprising a first combination of at least one of said collimator sheet elements;

The collimator sheet unit has a first surface and an opposite second surface, a plurality of through holes penetrating the first surface and the second surface, and a hole wall surrounding the through holes;

the hole wall of the collimator sheet unit has electric conduction capacity and can be connected with bias voltage;

the sheet structure of the collimator sheet unit enables the collimator sheet unit to have a combination function;

the first combined structure is provided with a first adjusting parameter set and is used for realizing process adjustment;

2. An electrically controlled collimator assembly as claimed in claim 1, characterized in that: the height between the first surface and the second surface of each collimator sheet-like element is 0.5cm to 15cm.

3. An electrically controlled collimator assembly as claimed in claim 1, characterized in that: the number of the collimator sheet units is 1, 2 or more than 3.

4. An electrically controlled collimator assembly as claimed in claim 1, characterized in that: the distance between the collimator sheet units is 0.1 cm-20 cm.

5. An electrically controlled collimator assembly as claimed in claim 1, characterized in that: the bias voltage of each collimator sheet unit is provided by an independent bias voltage power supply, and the bias voltage power supply provides direct current bias voltage or alternating current bias voltage.

6. An electrically controlled collimator assembly as claimed in claim 1, characterized in that: the constituent material of the hole wall of each collimator sheet unit includes a conductive material or an insulating material coated with a conductive film on the surface.

7. An electrically controlled collimator assembly as claimed in claim 1, characterized in that: the cross-sectional shape of the through hole of the collimator sheet unit includes a circle or a polygon.

8. An electrically controlled collimator assembly as set forth in claim 7, wherein: the distribution structure of the through holes on the collimator sheet unit in cross section comprises:

the cross-sectional shape and the cross-sectional area of the through holes in each area of the collimator sheet-like unit are the same;

Alternatively, the cross-sectional area of the through-hole of each region of the collimator sheet-like unit has a first variation structure;

the first variation includes:

the cross-sectional area of the through hole becomes first progressively larger or first regionally larger in a first direction from the center to the outer edge of the collimator sheet-like unit;

the first progressive enlargement means that the cross-sectional area of each through hole increases in sequence;

9. An electrically controlled collimator assembly as set forth in claim 7, wherein: the collimator sheet-like unit is circular in plan view, and the cross-sectional shape and the cross-sectional area of each through hole are the same or different in one annular region of the collimator sheet-like unit.

10. An electrically controlled collimator assembly as set forth in claim 7, wherein: the collimator sheet units are circular in top view, and the through holes are symmetrically distributed or asymmetrically distributed along the circle center of the collimator sheet units.

11. An electrically controlled collimator assembly as claimed in claim 1, characterized in that: the heights of all areas of the collimator sheet-shaped unit are equal; alternatively, the heights of the areas of the collimator sheet-like unit have a second variation structure;

the second variation includes:

the height of each region of the collimator sheet-like element becomes lower in a second progression or second regionalization in a first direction from the center to the outer edge of the collimator sheet-like element;

the second progressive lowering means that the heights of the hole walls become lower in sequence;

12. An electrically controlled collimator assembly as claimed in claim 1, characterized in that: the aspect ratio of each through hole on each collimator sheet-shaped unit or between the collimator sheet-shaped units is the same or different, the shape of each through hole is the same or different, and the size of each through hole is the same or different;

13. An electrically controlled collimator assembly as claimed in claim 1, characterized in that: in the first combined structure, the size of the area surrounded by the outer edges of the collimator sheet units is the same, and the collimator sheet units are arranged in parallel and aligned in the center.

14. An electrically controlled collimator assembly as claimed in claim 1, characterized in that: the process comprises PVD processes with process nodes of 40nm, 28nm, 14nm, 7nm and below 5 nm.

15. An electrically controlled collimator assembly as set forth in claim 5, wherein: the DC bias voltage provided by the bias power supply comprises a positive bias voltage, a negative bias voltage and a 0 bias voltage, the magnitude of the positive bias voltage is adjustable, the magnitude of the negative bias voltage is adjustable, and the waveform and the frequency of the AC bias voltage provided by the bias power supply are adjustable;

the bias voltage of each collimator sheet unit is selected or switched between the positive bias voltages with different magnitudes, the negative bias voltages with different magnitudes, the 0 bias voltage and the alternating bias voltages with different waveforms and frequencies according to process requirements;

16. An electrically controlled collimator assembly as claimed in claim 1, characterized in that: the collimator sheet unit is provided with a mounting part at the peripheral edge position, and the mounting part is of a conductive structure; the mounting part is used for realizing detachable fixed mounting and electric connection of the collimator sheet unit.

17. A substrate processing chamber, comprising: the target material and the wafer seat are placed in the reaction cavity, and the wafer seat also comprises an electric control collimator assembly;

the first combined structure is arranged inside the reaction cavity and is positioned between the target and the wafer bottom seat;

18. The substrate processing chamber of claim 17, wherein: the wafer base is a rotary wafer base and is used for rotating in the process to eliminate the transfer printing effect; the through holes of the collimator sheet units are asymmetrically arranged.

19. The substrate processing chamber of claim 18, wherein: the structure for fixing the wafer by the wafer base comprises: an electrostatic chuck or a vacuum chuck.

20. A method for debugging a process of a substrate processing chamber, comprising:

step one, manufacturing a plurality of collimator sheet units;

each collimator sheet unit has a first surface and an opposite second surface, a plurality of through holes penetrating the first surface and the second surface, and a hole wall surrounding the through holes;

step two, forming an electric control collimator assembly, wherein the electric control collimator assembly comprises a first combined structure formed by combining a plurality of collimator sheet-shaped units;

the first combination structure has a first set of adjustment parameters, the parameters of the first set of adjustment parameters including: the number of sheets of said collimator sheet elements, the bias of each said collimator sheet element, the configuration of said through-holes of each said collimator sheet element and the configuration of said hole walls, the height between the first and second surfaces of each said collimator sheet element, the spacing between each said collimator sheet element;

21. The method of claim 20, wherein: in the third step, the process includes PVD process.

22. The method of claim 21, wherein: in the third step, in the first combination structure, bias voltages of the collimator sheet units are independently set, and when more than 2 collimator sheet units are arranged in the first combination structure, an electric field type collimation structure is formed by combining bias voltages of all the collimator sheet units; the electric field type collimation structure realizes electric field focusing and ion acceleration on the deposited particles in the PVD process, and improves the straightness of the deposited particles.

23. The method of claim 22, wherein: the deposition particles of the PVD process comprise positive ion particles;

when the bias voltage of the collimator sheet unit is negative bias voltage, the collimator sheet unit can generate attraction effect on the positive ion particles;