阅读说明：本技术 用于预防或抑制发弧的化学气相沉积工具 (Chemical vapor deposition tool for preventing or inhibiting arcing ) 是由 崎山行则 卡尔·弗雷德里克·利瑟 文森特·布克哈特 于 2019-07-19 设计创作，主要内容包括：化学气相沉积(CVD)工具抑制或完全消除衬底基座和衬底之间的发弧。CVD工具包括直流(DC)偏置控制系统,其配置成将设置处理室中的衬底基座维持在与通过处理室中的等离子体所产生的DC偏压相同或基本上相同的DC偏压。通过将衬底基座和具有与等离子体相同的电位的衬底维持在相同或基本上相同的电压电位,抑制或完全消除发弧。(Chemical Vapor Deposition (CVD) tools suppress or completely eliminate arcing between the substrate pedestal and the substrate. The CVD tool includes a Direct Current (DC) bias control system configured to maintain a substrate pedestal disposed in the processing chamber at a DC bias that is the same or substantially the same as a DC bias generated by a plasma in the processing chamber. Arcing is suppressed or completely eliminated by maintaining the substrate pedestal and the substrate at the same or substantially the same voltage potential as the plasma.)

1. A Chemical Vapor Deposition (CVD) tool, comprising:

a processing chamber;

a substrate pedestal for supporting a substrate within the processing chamber;

a showerhead positioned within the processing chamber, the showerhead configured to dispense a gas that becomes a plasma within the processing chamber in response to a Radio Frequency (RF) potential, the plasma generating a DC bias; and

a Direct Current (DC) bias control system configured to maintain the substrate pedestal at a DC bias that is the same or substantially the same as the DC bias generated by the plasma in the processing chamber.

2. The CVD tool of claim 1, wherein the DC bias control system is further configured to adjust the DC bias of the substrate pedestal as the DC bias generated by the plasma changes.

3. The CVD tool of claim 2, wherein the DC bias control system adjusts the DC bias of the substrate pedestal by:

measuring a current along a current path between the plasma and a ground electrode; and

adjusting the DC bias of the substrate pedestal by maintaining the measured current at zero or a constant predetermined value.

4. The CVD tool of claim 3, wherein the DC bias control system is further configured to: using the measured current as a set point at the beginning of processing the substrate, and adjusting the DC bias of the substrate pedestal during subsequent processing of the substrate.

5. The CVD tool of claim 4, wherein the current path between the plasma and the electrode comprises one or more of:

(a) the substrate supported by the substrate pedestal;

(b) any thin film formed on the substrate;

(c) an electrode disposed on the substrate pedestal;

(d) a power supply coupled to the substrate pedestal; and

(e) the substrate pedestal.

6. The CVD tool of claim 4, wherein the resistance value is derived from a resistance of one or more of:

(a) the substrate;

(b) any thin film formed on the substrate;

(c) an electrode disposed on the substrate pedestal; and

(d) a power supply coupled to the substrate pedestal.

7. The CVD tool of claim 1, wherein the substrate pedestal is an electrostatic chuck (ESC) type substrate pedestal comprising first and second electrodes maintained at opposing clamping potentials, wherein the opposing clamping potentials are adjusted by the same or substantially the same DC bias as generated by the plasma in the processing chamber.

8. The CVD tool of claim 1, wherein the substrate pedestal comprises an RF electrode for providing the RF potential to the plasma in the processing chamber.

9. The CVD tool of claim 8, wherein the RF electrode is adjusted by the same or substantially the same DC bias as generated by the plasma in the processing chamber.

10. The CVD tool of claim 1, wherein the DC bias control system comprises:

a current measuring device for measuring a current between the plasma and an electrode; and

a controlled power supply responsive to the current measuring device to control a DC bias to an electrode disposed on the substrate pedestal.

11. The CVD tool of claim 7, wherein the electrodes disposed on the substrate pedestal are positive and negative electrodes for electrostatically clamping the substrate to the substrate pedestal.

12. The CVD tool of claim 1, wherein the processing chamber further comprises two or more substrate susceptors.

13. The CVD tool of claim 14, wherein the DC bias control system is further configured to maintain the two or more substrate pedestals at the same or substantially the same DC bias as the plasma in the processing chamber.

14. The CVD tool of claim 1, wherein substantially the same means that the DC bias generated by the plasma and the substrate pedestal have a voltage difference of 10.0 volts or less.

15. The CVD tool of claim 1, wherein substantially the same means that the DC bias generated by the plasma and the substrate pedestal have a voltage difference of 0.1 volts or less.

16. A Chemical Vapor Deposition (CVD) tool comprising a Direct Current (DC) bias control system configured to maintain a substrate pedestal disposed in a processing chamber at a same or substantially the same DC bias as a DC bias generated by a plasma in the processing chamber.

17. The CVD tool of claim 16, wherein the substrate pedestal comprises an electrostatic chuck (ESC) electrode of opposite polarity for clamping a substrate to the substrate pedestal and the DC bias is applied to the ESC electrode of opposite polarity.

18. The CVD tool of claim 16, wherein the DC bias control system adjusts the DC bias as the DC bias generated by the plasma in the processing chamber changes.

19. The CVD tool of claim 16, wherein the DC bias control system comprises:

a current measuring device for measuring a current between the plasma and an electrode;

an ESC power supply for applying a DC bias compensation to an electrode disposed on the substrate pedestal, the DC bias compensation being commensurate with the measured current.

20. The CVD tool of claim 19, wherein a current path for the current between the plasma and the electrode comprises one or more of:

(a) a substrate supported by the substrate pedestal;

(b) any thin film formed on the substrate;

(c) an electrode disposed on the substrate pedestal;

(d) a power supply coupled to the substrate pedestal; and

(e) the substrate pedestal.

21. The CVD tool of claim 19, wherein the resistance value is derived from a resistance of one or more of:

(a) a substrate;

(b) any thin film formed on the substrate;

(c) an electrode disposed on the substrate pedestal; and

(d) a power supply coupled to the substrate pedestal.

22. The CVD tool of claim 21, wherein substantially the same means that the DC bias generated by the plasma and the substrate pedestal have a voltage difference of 10.0 volts or less.

23. The CVD tool of claim 21, wherein substantially the same means that the DC bias generated by the plasma and the substrate pedestal has a voltage difference of 0.1 volts or less.

Background

Plasma Enhanced Chemical Vapor Deposition (PECVD) tools are used to deposit thin films on substrates. CVD tools typically include a process chamber, a substrate pedestal for supporting a substrate in the process chamber, and a showerhead. During operation, the showerhead dispenses a reactive gas over the surface of the substrate to be processed. A Radio Frequency (RF) potential is applied between two electrodes, typically disposed on the showerhead and/or the substrate pedestal, to generate a plasma. The excited electrons ionize or dissociate (e.g., "crack") the reactant gas from the plasma, producing chemically reactive radicals. When these radicals react, they deposit and form a thin film on the substrate.

Arcing (arcing) is a well-known electrical phenomenon caused by the breakdown of a generally non-conductive gas provided in a gap between two surfaces at different voltage potentials. When arcing occurs, the non-conductive gas breaks down and a strong current or discharge momentarily jumps across the gap between the two surfaces.

Arcing is a significant problem for PECVD tools. A resistive material (e.g., a dielectric film) is typically provided between the substrate and the pedestal. During operation of the tool, when an RF potential is applied, the plasma and the substrate in the processing chamber inherently generate a Direct Current (DC) bias. As a result, a non-zero DC voltage exists between the substrate and the substrate pedestal due to the resistive material.

If the difference in DC voltage exceeds a certain threshold, an electrical breakdown may occur in the gas between the substrate and the substrate pedestal. The magnitude of the DC bias tends to increase when a thin film is deposited on the substrate. As a result, the possibility of electrical breakdown is greatly increased. For certain types of substrates (e.g., semiconductor wafers), a burst of electrical discharge or arcing may damage sensitive circuitry. Damaging the circuitry on the semiconductor wafer reduces yield, resulting in potentially significant manufacturing losses and increased cost.

Therefore, there is a need for a CVD tool that inhibits or completely eliminates arcing between the substrate and the substrate pedestal.

Disclosure of Invention

A Chemical Vapor Deposition (CVD) tool is disclosed that suppresses or completely eliminates arcing between a substrate pedestal and a substrate. The tool includes a process chamber, a substrate pedestal for supporting a substrate within the process chamber, and a showerhead positioned within the process chamber. The showerhead is configured to dispense a gas that is converted to a plasma that generates a DC bias in response to a Radio Frequency (RF) potential. The tool also includes a Direct Current (DC) bias control system configured to maintain the substrate pedestal at a DC bias that is the same or substantially the same as a DC bias generated by the plasma.

In a non-exclusive embodiment, the DC bias control system adjusts the DC bias of the substrate pedestal by measuring a DC current between the plasma and the substrate pedestal and maintaining the DC current constant while the resistance between ground and the substrate remains constant.

In another non-exclusive embodiment, the DC bias control system is further configured to measure a DC current at the beginning of processing of the substrate, and then adjust the DC bias to maintain the measured DC current for the remainder of the processing of the substrate in order to compensate for drift in the resistance.

In various non-exclusive embodiments, the current path between the plasma and the electrode includes one or more of: (a) a substrate supported by the substrate pedestal, (b) any thin films formed on the substrate, (c) the substrate pedestal, (d) a power supply coupled to the substrate pedestal. The resistance is comprised of one or more of: (f) a substrate, (g) any thin film formed on the substrate, (h) a substrate pedestal, and (i) a resistive component in a power supply system coupled to the substrate pedestal.

Drawings

The present application, together with its advantages, may be best understood by reference to the following description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a block diagram of a Chemical Vapor Deposition (CVD) chamber according to a non-exclusive embodiment of the present invention.

Fig. 2A and 2B are top and cross-sectional views of a substrate pedestal according to a non-exclusive embodiment of the present invention.

Fig. 3 is a schematic diagram illustrating how arcing is suppressed or prevented according to a non-exclusive embodiment of the invention.

Fig. 4 is a graph illustrating the unpredictability of the DC bias generated by the plasma in the tool over time.

FIG. 5 is a block diagram illustrating an active DC bias control system for a substrate pedestal according to the present invention.

Figure 6 is a schematic view of a CVD chamber with multiple substrate susceptors according to a non-exclusive embodiment of the present invention.

Fig. 7 is a block diagram of a system controller for controlling a CVD tool according to a non-exclusive embodiment of the present invention.

In the drawings, like reference numerals are sometimes used to refer to like structural elements. It is also to be understood that the descriptions in the figures are schematic and are not necessarily drawn to scale.

Detailed Description

The present application will now be described in detail with reference to a few non-exclusive embodiments thereof as illustrated in the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. It will be apparent, however, to one skilled in the art, that the present disclosure may be practiced without some or all of these specific details. In other instances, well known process steps and/or structures have not been described in detail in order to not unnecessarily obscure the present invention.

Referring to FIG. 1, a block diagram of a Chemical Vapor Deposition (CVD) tool 10 is shown. The tool 10 includes a processing chamber 12, a showerhead 14, a substrate pedestal 16 for positioning a substrate 18 to be processed, a Radio Frequency (RF) source generator 20, a gas source 22, a system controller 24, an ESC power supply 26 coupled to the substrate pedestal 16, and a Direct Current (DC) bias control system 28. In various embodiments, the CVD tool may be a Plasma Enhanced (PECVD), Plasma Enhanced Atomic Layer Deposition (PEALD), or any other type of CVD tool that uses plasma.

During operation, reactant gases are supplied from gas source 22 through showerhead 14 into process chamber 12. Within showerhead 14, gas is dispensed into chamber 12 through one or more plenums (not shown) into the region above the surface of substrate 18. The RF potential generated by RF generator 20 is applied to one or more electrodes (not visible) on substrate pedestal 16. The RF potential causes the gas to ionize and generate a plasma inside the process chamber 12. Within the plasma, the excited electrons dissociate (i.e., "cleave") from the reactant gas, thereby generating chemically reactive radicals. When these radicals react, they deposit and form a thin film on the substrate 18.

In various embodiments, RF generator 20 may be a single RF generator or multiple RF generators capable of generating high, medium, and/or low RF frequencies. For example, at high frequencies, RF generator 20 may generate frequencies ranging from 2-100MHz, and preferably 13.56MHz or 27 MHz. When generating the low frequency, the range is 50KHz to 2MHz, and preferably 350KHz to 600 KHz. In alternative embodiments, the RF source may be coupled to an RF electrode disposed on the showerhead 14 instead of an RF electrode disposed on the substrate pedestal 16, or to both the showerhead 14 and the substrate pedestal 16.

The system controller 24 generally serves to control the overall operation of the CVD tool 10 and to manage process conditions during deposition, post-deposition, and/or other process operations.

In a non-exclusive embodiment, the substrate pedestal 16 is an electrostatic chuck (ESC) type substrate pedestal. ESC power supply 26 is provided to supply an opposing voltage to an electrode (not shown in fig. 1) embedded in the clamping surface of substrate pedestal 16, the voltage being of sufficient magnitude to generate the electrostatic force required to clamp substrate 18.

When an RF potential is applied to the reaction gas in the process chamber 12, plasma is generated. In response to the RF potential, the plasma generates a DC bias, typically in the range of (0) volts to (-100) volts. In the event that substrate 18 is exposed to a plasma, the substrate generates the same or substantially the same DC bias as the plasma. Generally, the substrate pedestal 16 is typically maintained at different voltages. The voltage difference between substrate pedestal 16 and substrate 18 is prone to arcing.

A DC bias control system 28 is provided to maintain substrate pedestal 16 at the same or substantially the same DC bias as generated by the plasma and substrate 18. Thus, the voltage difference between substrate pedestal 16 and substrate 18 is zero or near zero. As a result, arcing between the substrate pedestal 16 and the substrate 18 is suppressed or completely eliminated.

Referring to fig. 2A and 2B, a top view and a cross-sectional view of a non-exclusive embodiment of the substrate pedestal 16 are shown. In this particular embodiment, the body 29 of the substrate pedestal 16 is made of a non-conductive ceramic material, such as aluminum nitride. An electrostatic chuck (ESC) surface 30 for holding the substrate 18 is embedded in the substrate pedestal 16.

As best illustrated in fig. 2A, the electrode 30 is embedded in the substrate pedestal 16 and includes a pair of "D-shaped" ESC clamp electrodes 32A and 32B. During clamping, voltages of opposite polarity (e.g., +/-500 volts) are applied to the two electrodes 32A and 32B, respectively. The resulting electrostatic force clamps the substrate 18 to the clamping surface 30 of the substrate pedestal 16.

The substrate pedestal 16 also includes an RF electrode 34 embedded in the top surface 30 and disposed around the periphery of the top surface 30 and through the center thereof. Electrodes 32A, 32B, and 34 are coupled to RF source 20 and are configured to provide the RF potential necessary to ionize the reactant gases supplied to process chamber 12 and generate a plasma. As best illustrated in fig. 2B, the cross-sectional view shows ESC clamp electrodes 32A and 32B, and RF electrodes 32A, 32B and 34 embedded in the body 29 of the substrate pedestal 16.

To inhibit or prevent arcing, the DC bias control system 26 provides a bias voltage to the left and right electrodes 32A and 32B. For example, consider an ESC clamping voltage of (+/-500 volts) applied to electrodes 32A and 32B, respectivelyAnd (6) pressing. If the plasma in the process chamber 12 produces a bias of (-10 volts), then the same or similar magnitude of bias voltage V will be applied_DCTo electrodes 32A and 32B. In other words, electrode 32A is maintained at 490 volts (500-10), and electrode 32B is maintained at-510 volts (-500-10). In another non-exclusive embodiment, the same bias voltage V_DC(e.g., -10V) may also be applied to electrode 34.

Since the voltage difference between the two electrodes 32A and 32B remains the same, the bias voltage V_DCThe ESC clamping force is not affected. However, the voltage difference between the substrate pedestal 16 and the substrate 18 is reduced to zero or very close to zero, thereby inhibiting or completely eliminating arcing.

Referring to fig. 3, a schematic diagram showing how arcing is prevented or suppressed is illustrated. The showerhead 14 introduces one or more reactive gases into the process chamber 12. The RF potential provided by electrode 34 embedded in substrate pedestal 16 causes ionization of the reactant gas, thereby generating a plasma.

In this particular example, a conductive film 36, such as a metal or conductive carbon layer, is deposited over the dielectric layer 38. During deposition, layers or films 36, 38 are formed on both the top surface of substrate 18 and the surrounding portions of substrate pedestal 16. When the conductive layer 36 is formed, negative surface charges, represented by the letter "e", are accumulated on the surface of the substrate 18.

DC bias voltage "V" identical to the DC bias voltage generated by the plasma_DC"electrodes 32A and 32B (not shown) applied to substrate pedestal 16. Because the voltage difference between substrate 18 and substrate pedestal 16 is the same or substantially the same, surface charge "e" on substrate 18 is not attracted to substrate pedestal 16. As a result, arcing is suppressed or completely eliminated, particularly in the region depicted by the ellipse 40, which tends to be the most prone location for arcing.

During processing of substrate 18 in process chamber 12, the DC bias generated by the plasma tends to vary unpredictably over time. For example, during deposition of a conductive (e.g., carbon) layer onto a semiconductor wafer, the plasma "sees" the conductive layer as an electrode. Over time, the layer tends to gradually widen and thicken on the peripheral top surface of the wafer and substrate pedestal 16 during the extended deposition process. Due to this growth, the plasma tends to spread out, causing the DC bias generated by the plasma to change. However, the DC bias generated by the plasma is generally not linear. As a result, it is difficult to predict how the DC bias generated by the plasma will vary over time.

Fig. 4 is an exemplary diagram illustrating unpredictability of the DC bias generated by the plasma in a CVD tool during deposition. The graph shows that over time, the DC bias tends to decrease (e.g., from about-5.0 volts to about-20.0 volts). However, the reduction is not linear. Thus, the figure shows the bias voltage V if it is to be fixed_DCApplied to electrodes 32A, 32B, and/or 34, a voltage differential may sometimes exist between substrate 18 and substrate pedestal 16 as the DC bias of the plasma is varied. Substrate 18 is prone to arcing whenever a voltage differential exists. The graph shown is merely illustrative to show the non-linearity of the DC bias reduction. It will be appreciated that in actual implementations the figures will vary greatly, but will generally show a reduction in DC bias.

When there is a non-zero voltage difference, a DC current flows between the plasma and the ground electrode due to the finite resistance between the plasma and the ground electrode. The current path between the plasma and the electrode includes one or more of: (a) a substrate 18 supported by the substrate pedestal 16; (b) any thin film formed on substrate 18; (c) electrodes 32A, 32B, 34 provided on the substrate base 16; (d) a power supply 26 coupled to substrate pedestal 16; and (e) a substrate pedestal 16.

The resistance is comprised of one or more of the following provided on the current path defined above: (a) a substrate 18; (b) any thin film formed on substrate 18; (c) electrodes 32A, 32B, and 34 disposed on the substrate base 16; and a power supply 26 coupled to substrate pedestal 16.

As described above, as the conditions within the process chamber 12 change, the DC bias of the plasma also changes. When the resistance is fixed, a change in the measured current will indicate a change in the DC bias of the plasma. As a result, Δ V_DCThe change in value is comparable to the change in DC bias voltage generated by the plasma over time. By continuously measuring Δ V_DCAnd applied to electrodes 32A, 32B and/or 34, the DC bias of the substrate pedestal can substantially track the DC bias generated by the plasma and substrate 18 as processing conditions change. In other words, as conditions change in the process chamber 12, the voltage difference between the substrate pedestal 16 and the substrate 18 remains at or near zero.

Referring to fig. 5, a block diagram is shown illustrating the DC bias control system 28. System 28 includes a current measurement device 50 and an ESC power supply 26. The current measuring device 50 measures a sample of the current between the plasma and the ground electrode. DC power supply 52 adjusts the bias voltage applied to electrodes 32A, 32B, and/or 34 via ESC power supply 26 to maintain a constant current. By maintaining a constant current, the voltage difference between the substrate 18 and the substrate pedestal is zero or near zero.

In various embodiments, the predetermined sampling rate for measuring the current samples may vary widely. For example, the sampling rate may be any point ranging from 1ms to 10 seconds. Generally, the higher the sampling rate, the more precisely the bias voltage can be adjusted to track changes in the actual DC bias voltage generated by the plasma. As a result, it is possible to achieve a higher degree of arcing suppression.

Based on the foregoing, there are many ways to inhibit or completely prevent arcing. For example:

by maintaining the voltage between the substrate 18 and the substrate pedestal 16 constant (zero or near zero volts), arcing may be eliminated or significantly limited. However, as the DC bias of the plasma changes over time, the voltage difference between the susceptor and the substrate may increase. As a result, the chances of arcing may also increase.

By using a feedback loop to measure the sampled current and control the DC bias supply 52 to adjust the bias voltage applied to the electrodes 32A, 32B and/or 34 via ESC supply 26, the measured current can be maintained at a predefined constant value. This method is effective even if the DC bias of the plasma changes over time, but is susceptible to changes in resistance if they change. For example, if the resistance varies from one substrate to the next, or when multiple layers are added to the substrate, the likelihood of arcing increases.

The current is measured once and used as a set point for each substrate. Thereafter, the feedback loop described above is used to adjust the bias voltage applied to the electrodes 32A, 32B and/or 34. For the next substrate, the set point is again measured and the bias voltage is adjusted accordingly. By measuring the current for each substrate, the set point is updated to compensate for drift in the system. With this arrangement, the chance of arcing is significantly suppressed even when the DC bias of the plasma and/or the conditions in the chamber 12 change over time.

The ability to measure DC current and adjust and apply a DC bias to the electrodes 32A, 32B and/or 34 of the substrate pedestal 16 provides a number of advantages. First, the voltage difference between substrate pedestal 16 and substrate 18 remains at or near zero for the duration that substrate 18 is processed in chamber 12. Second, when one substrate 18 is replaced with another substrate 18 for processing, the current can be measured and the DC bias adjusted to match the current conditions in the processing chamber 12. Third, the DC bias control system 28 has the ability to adjust the DC bias voltage independent of the tool 10 and/or the process chamber 12. Thus, any variation from one CVD tool 10 to the next or from one process chamber 12 to the next is not an issue because DC bias control system 28 has the ability to adjust the DC bias voltage regardless of how conditions may vary from one tool to the next.

Referring to FIG. 6, a schematic view of a CVD chamber 12 having a plurality of substrate pedestals 16 is illustrated. In this particular embodiment, the CVD tool 10 is referred to as a "four station" (quad) tool because it has four substrate pedestals 16A-16D in the process chamber 12. Thus, DC bias control system 28 provides four (A-D) bias voltages Δ V_DC(+/-), each bias voltage is calculated for the four substrate pedestals 16A-16D, respectively, as described above. It should be understood that the four-station tool 10 as illustrated is merely exemplary and should not be construed as limiting in some way. The system for suppressing or eliminating arcing may be used in a CVD tool having any number of substrate susceptors.

Fig. 7 is a high level block diagram showing the system controller 24. The computer system 24 may have many physical forms ranging from an integrated circuit, a printed circuit board, a small handheld device, a personal computer, a server, a supercomputer, any of which may have one or more processors. Computer system 24 can also include an electronic display device 804 (for displaying graphics, text, and other data), a non-transitory main memory 806 (e.g., Random Access Memory (RAM)), a storage device 808 (e.g., a hard disk drive), a removable storage device 810 (e.g., an optical disk drive), a user interface device 812 (e.g., a keyboard, touch screen, keypad, mouse, or other positioning device, etc.), and a communication interface 814 (e.g., a wireless network interface). Communication interface 814 enables software and data to be transferred between system controller 24 and external devices via a link. System controller 24 may also include a communication infrastructure 816 (e.g., a communication bus, cross-over bar, or network), to which the aforementioned devices/modules are connected.

The term "non-transitory computer-readable medium" is used generically to refer to media such as main memory, secondary memory, removable storage, and storage devices (e.g., hard disk, flash memory, hard drive memory, CD-ROM, and other forms of permanent memory), and should not be construed to cover transitory subject matter such as a carrier wave or signal.

In certain embodiments, system controller 24, running or executing system software or code, controls all or at least most of the activities of tool 10 including activities such as controlling the timing of processing operations, the frequency and power of operation of RF generator 20, the pressure within process chamber 12, the flow rate, concentration and temperature of gases flowing into process chamber 12 and relative mixing thereof, and the temperature of substrate 18 supported by substrate holder 16.

Information transferred via communications interface 814 may be in the form of signals, e.g., electronic, electromagnetic, optical, or other signals, that are received by communications interface 814 via a communications link that carries the signals and that may be implemented using wire or cable, fiber optics, a telephone line, a cellular telephone link, a radio frequency link, and/or other communications channels. With such a communication interface, it is contemplated that the one or more processors 802 can receive information from a network or can output information to a network. Additionally, method embodiments may execute solely on the processor or may execute over a network such as the Internet in conjunction with remote processors that share a portion of the processing.

It is to be understood that the embodiments provided herein are merely exemplary, and should not be construed as limiting in any way. In general, this application is intended to cover any sprinkler having at least two sets of orifices defining two spiral patterns and two plenums for the two patterns, respectively.

Although only some embodiments have been described in detail, it should be understood that the present application may be embodied in many other forms without departing from the spirit or scope of the disclosure provided herein. For example, the substrate may be a semiconductor wafer, a discrete semiconductor device, a flat panel display, or any other type of workpiece.

Accordingly, the present embodiments are to be considered as illustrative and not restrictive, and the details given herein are not to be limited, but may be modified within the scope and equivalents of the appended claims.