High frequency RF generator and DC pulse

Abstract

Nanosecond pulse generator systems are disclosed. In some embodiments, a nanosecond pulse provides can include a high voltage power supply; a nanosecond pulse generator electrically coupled to the high voltage power supply, the nanosecond pulse generator switching a voltage from the high voltage power supply at a high frequency; a transformer having a primary side and a secondary side, the nanosecond pulse generator electrically coupled to the primary side of the transformer; and an output electrically coupled to the transformer to produce a waveform. In some embodiments, the waveform includes a plurality of high voltage pulses having a pulse amplitude greater than about 2 kV, a pulse width, and a pulse repetition frequency; and a sinusoidal waveform having a waveform frequency and a waveform amplitude greater than 100 V.

Description

Background Technology

[0001] Some plasma systems include at least two power sources. One generates a high-frequency waveform, which can be used to generate plasma within the plasma chamber. The other generates a high-voltage pulse, which accelerates the charged plasma particles towards the wafer within the plasma chamber. These two power sources are typically separate and distinct from each other. Summary of the Invention

[0002] The power supply is disclosed. In some embodiments, the nanosecond pulse supply may include a high-voltage power supply; a nanosecond pulse generator electrically coupled to the high-voltage power supply, the nanosecond pulse generator switching the voltage from the high-voltage power supply at a high frequency; a transformer having a primary side and a secondary side, the nanosecond pulse generator being electrically coupled to the primary side of the transformer; and an output electrically coupled to the transformer to generate a waveform. In some embodiments, the waveform includes a plurality of high-voltage pulses having a pulse amplitude, pulse width, and pulse repetition frequency greater than approximately 2 kV; and a sinusoidal waveform having a waveform frequency and a waveform amplitude greater than 100 V, wherein the waveform amplitude is less than the pulse amplitude; and wherein the pulse repetition frequency is less than the waveform frequency.

[0003] In some embodiments, the waveform frequency is greater than approximately 10 MHz.

[0004] In some embodiments, the power supply includes a stray inductor and a stray capacitor, wherein the waveform frequency and / or the waveform amplitude are at least partially dependent on one and / or both of the stray inductor and the stray capacitor.

[0005] In some embodiments, the waveform frequency and / or the waveform amplitude depend at least in part on the pulse width.

[0006] In some embodiments, the power supply includes a stray inductor having an inductance value of less than approximately 1.8 μH. In some embodiments, the power supply includes a stray inductor having an inductance value of less than approximately 400 nH. In some embodiments, the power supply includes a stray capacitor having a capacitance value of less than approximately 20 nF.

[0007] In some embodiments, the output is coupled to a plasma chamber, wherein the sinusoidal waveform generates plasma within the plasma chamber and the plurality of high-voltage pulses accelerate plasma particles within the plasma.

[0008] In some embodiments, the pulse amplitude is greater than about 5 kV, and each of the plurality of high-frequency pulses has a pulse rise time of less than about 20 ns.

[0009] A power supply is disclosed. In some embodiments, the power supply may include a high-voltage power supply; a nanosecond pulse generator electrically coupled to the high-voltage power supply, the nanosecond pulse generator switching voltages from the high-voltage power supply at a high frequency; a transformer having a primary side and a secondary side, the nanosecond pulse generator being electrically coupled to the primary side of the transformer; and an output electrically coupled to the transformer to generate a waveform. The waveform includes a plurality of high-voltage pulses having pulse amplitude, pulse width, and pulse repetition frequency; and a sinusoidal waveform having a waveform frequency and waveform amplitude. The power supply has stray capacitance and / or stray inductance, the stray capacitance having a capacitance value of less than approximately 20 nF measured from the output, and the stray inductance having an inductance value of less than approximately 400 nH measured from the output.

[0010] In some embodiments, the waveform frequency and / or the waveform amplitude depend at least in part on one and / or both of the stray inductance and the stray capacitance.

[0011] In some embodiments, the waveform frequency and / or the waveform amplitude depend at least in part on the pulse width.

[0012] In some embodiments, the pulse amplitude is greater than about 5 kV, and each of the plurality of high-frequency pulses has a pulse rise time of less than about 20 ns.

[0013] In some embodiments, the waveform amplitude is less than the pulse amplitude.

[0014] In some embodiments, the pulse repetition frequency is less than the waveform frequency.

[0015] In some embodiments, the waveform frequency is between approximately 2 MHz and 20 MHz.

[0016] In some embodiments, the power supply may also include an energy recovery circuit electrically coupled to the secondary side of the transformer. The energy recovery circuit may include an energy recovery inductor electrically coupled to the high-voltage power supply; a crowbar diode configured to be connected in parallel with the secondary side of the transformer; and a second diode configured to be connected in series with the energy recovery inductor and to direct current from the load through the energy recovery inductor to the high-voltage power supply.

[0017] A semiconductor plasma system is also disclosed. The semiconductor plasma system may include a plasma chamber and a high-voltage power supply. The high-voltage power supply may include: a high-voltage power supply; a nanosecond pulse generator electrically coupled to the high-voltage power supply, the nanosecond pulse generator switching the voltage from the high-voltage power supply at a high frequency; a transformer having a primary side and a secondary side, the nanosecond pulse generator being electrically coupled to the primary side of the transformer; and an output electrically coupled to the transformer and the plasma chamber, the output generating a waveform within the plasma chamber. The waveform includes a sinusoidal waveform configured to generate plasma within the plasma chamber, the sinusoidal waveform having a waveform frequency and a waveform amplitude greater than 100V; and / or multiple high-voltage pulses that accelerate plasma particles within the plasma chamber, the high-voltage pulses having a pulse amplitude, pulse width, and pulse repetition frequency greater than approximately 2kV.

[0018] In some embodiments, the power supply has stray capacitance and / or stray inductance, wherein the waveform frequency and / or the waveform amplitude are at least partially dependent on one and / or both of the stray inductance and the stray capacitance.

[0019] In some embodiments, the waveform frequency and / or the waveform amplitude depend at least in part on the pulse width.

[0020] In some embodiments, the plasma chamber generates a plasma shell (plasmasheath) with shell capacitance, wherein the waveform frequency and / or the waveform amplitude depend on the shell capacitance.

[0021] In some embodiments, the power supply includes a stray inductor having an inductance value of less than approximately 400 nH. In some embodiments, the power supply includes a stray capacitor having a capacitance value of less than approximately 20 nF. In some embodiments, the amplitude of the pulse is greater than approximately 5 kV, and each of the plurality of high-frequency pulses has a pulse rise time of less than approximately 40 ns.

[0022] In some embodiments, the waveform amplitude is less than the pulse amplitude.

[0023] In some embodiments, the pulse repetition frequency is less than the waveform frequency. In some embodiments, the waveform frequency is greater than approximately 10 MHz.

[0024] In some embodiments, the power supply further includes an energy recovery circuit electrically coupled to the secondary side of the transformer. The energy recovery circuit may include an energy recovery inductor electrically coupled to the high-voltage power supply; a crowbar diode configured to be connected in parallel with the secondary side of the transformer; and a second diode configured to be connected in series with the energy recovery inductor and for directing current from the load through the energy recovery inductor to the high-voltage power supply.

[0025] The different embodiments described in the Summary of the Invention and this document are not intended to limit or define the scope of this disclosure or the claims. Attached Figure Description

[0026] Figure 1 This is a circuit diagram of a nanosecond pulser system with an energy recovery circuit driving a load stage, according to some embodiments.

[0027] Figure 2 This is a circuit diagram of a nanosecond pulser system having a resistive output stage driving a load stage according to some embodiments.

[0028] Figure 3 Three waveforms generated by a nanosecond pulser system according to some embodiments are shown;

[0029] Figure 4 Three waveforms generated by a nanosecond pulser system according to some embodiments are shown;

[0030] Figure 5 Three waveforms generated by a nanosecond pulser system according to some embodiments are shown;

[0031] Figure 6 Three waveforms generated by a nanosecond pulser system according to some embodiments are shown;

[0032] Figure 7 Three waveforms generated by a nanosecond pulser system according to some embodiments are shown;

[0033] Figure 8 Three waveforms generated by a nanosecond pulser system according to some embodiments are shown. Detailed Implementation

[0034] Some embodiments include a plasma system that introduces high-frequency waveforms and high-voltage pulses within a plasma chamber. The high-frequency waveforms can be used, for example, to generate plasma within the plasma chamber. The high-voltage pulses can be used, for example, to accelerate charged plasma particles toward a wafer within the plasma chamber. In some embodiments, a single nanosecond pulse system can be used to generate both the high-frequency waveforms and the high-voltage pulses. Such a plasma system, for example, using a single power supply, can simultaneously replace both an RF power supply and a pulsed power supply.

[0035] In some embodiments, an edge ring electrode is employed, whereby a first nanosecond pulser system can be coupled to the main electrode within the plasma chamber and a second nanosecond pulser system can be coupled to the edge ring. In some embodiments and configurations, the second nanosecond pulser system may generate only high-voltage pulses. In some configurations, the second nanosecond pulser system may generate both high-frequency waveforms and high-voltage pulses.

[0036] For example, a nanosecond pulser system can include any power source capable of generating high-voltage pulses (e.g., voltages greater than 1kV, 10kV, 20kV, 50kV, 100kV, etc.), at high frequencies (e.g., frequencies greater than 1kHz, 10kHz, 100kHz, 200kHz, 500kHz, 1MHz, etc.), having fast rise times (e.g., rise times less than approximately 1ns, 10ns, 50ns, 100ns, 250ns, 500ns, 1000ns, etc.), having fast fall times (e.g., fall times less than approximately 1ns, 10ns, 50ns, 100ns, 250ns, 500ns, 1000ns, etc.), and / or short pulse widths (e.g., pulse widths less than approximately 1000ns, 500ns, 250ns, 100ns, 20ns, etc.).

[0037] For example, a nanosecond pulse generator system can be called a pulse generator, pulse bias generator, nanosecond pulse generator, square wave generator, etc.

[0038] Figure 1 This is a circuit diagram of a nanosecond pulser system 100 driving a load stage 106 according to some embodiments. Although a specific load stage 106 is shown, other loads may be used.

[0039] In some embodiments, load stage 106 may represent an idealized or functional circuit for a semiconductor processing chamber, such as a plasma deposition system, a semiconductor manufacturing system, a plasma sputtering system, etc. For example, capacitor 12 may represent the capacitance value of an electrostatic chuck on which a semiconductor process wafer may be located. For example, the chuck may include a dielectric material (e.g., alumina, or other ceramic material and conductors encapsulated within the dielectric material). For example, capacitor 23 may have a small capacitance value (e.g., approximately 10 pF, 100 pF, 500 pF, 1 nF, 10 nF, 100 nF, etc.).

[0040] For example, capacitor 13 could represent the shell capacitance between the plasma and the wafer. For example, resistor 56 could represent the shell resistance between the plasma and the wafer. For example, current source 12 could represent the shell inductance between the plasma and the wafer. For example, capacitor 23 or capacitor 13 could have small capacitance values ​​(e.g., approximately 10pF, 100pF, 500pF, 1nF, 10nF, 100nF, etc.).

[0041] For example, capacitor 18 can represent the plasma shell capacitance to the chamber wall. For example, resistor 57 can represent the shell resistance between the plasma and the chamber wall. For example, current source 11 can represent the ion current in the plasma. For example, capacitor 23 or capacitor 18 can have small capacitance values ​​(e.g., approximately 10 pF, 100 pF, 500 pF, 1 nF, 10 nF, 100 nF, etc.).

[0042] In some embodiments, the plasma voltage may be the voltage measured from ground to circuit point 123; the wafer voltage may be the voltage measured from ground to circuit point 122 and may represent the voltage on the wafer surface; the card voltage may be the voltage measured from ground to circuit point 121; the electrode voltage may be the voltage measured from ground to circuit point 124 (e.g., on the electrode); and the input voltage may be the voltage measured from ground to circuit point 125.

[0043] In this example, the DC bias circuit 104 does not include any bias compensation. The DC bias circuit 104 includes an offset supply voltage 90, which can bias the output voltage, for example, in the forward or reverse direction. In some embodiments, the offset supply voltage 90 can be adjusted to modify the potential between the wafer voltage and the chuck voltage. In some embodiments, the offset supply voltage 90 can have voltages such as approximately ±5kV, ±4kV, ±3kV, ±2kV, ±1kV, etc.

[0044] In some embodiments, bias capacitor 20 can isolate (or separate) the DC bias voltage from other circuit elements. For example, bias capacitor 21 can allow a potential shift from one part of the circuit to another. In some embodiments, this potential shift can ensure that the electrostatic force holding the wafer on the chuck is below an average threshold. Resistor 52 can isolate the DC bias power supply from the high-voltage pulse output from nanosecond pulser stage 101.

[0045] For example, the bias capacitor can be represented by a capacitance value less than approximately 100pF, 10pF, 1pF, 100μF, 10μF, 1μF, etc. For example, the resistor 52 can have a high resistance, such as, for example, approximately 1kOhm, 10kOhm, 100kOhm, 1MOhm, 10MOhm, 100Mohm, etc.

[0046] For example, resistor R13 can represent the resistance of a lead or transmission line that connects the output of a high-voltage power system to an electrode (e.g., load stage 106). Stray capacitance may also be present in the lead or transmission line.

[0047] In some embodiments, the nanosecond pulser stage 101 may generate pulses with high pulse voltages (e.g., voltages greater than 1kV, 10kV, 20kV, 50kV, 100kV, etc.), high frequencies (e.g., frequencies greater than 1kHz, 10kHz, 100kHz, 200kHz, 500kHz, 1MHz, etc.), fast rise times (e.g., rise times less than approximately 1ns, 10ns, 50ns, 100ns, 250ns, 500ns, 1,000ns, etc.), fast fall times (e.g., fall times less than approximately 1ns, 10ns, 50ns, 100ns, 250ns, 500ns, 1,000ns), and / or short pulse widths (e.g., pulse widths less than approximately 1,000ns, 500ns, 250ns, 100ns, 20ns).

[0048] For example, nanosecond pulser stage 101 may include all or any part of the device described in U.S. Patent Application No. 14 / 542,486 entitled “High Voltage Nanosecond Pulse,” which is incorporated herein by reference for all purposes; or all or any part of the device described in U.S. Patent Application No. 14 / 635,991 entitled “Electrically Isolated Variable Output Pulse Generator Disclosure,” which is incorporated herein by reference for all purposes; or all or any part of the device described in U.S. Patent Application No. 14 / 798,154 entitled “High Voltage Nanosecond Pulse with Variable Pulse Width and Pulse Repetition Frequency,” which is incorporated herein by reference for all purposes.

[0049] In some embodiments, the nanosecond pulser stage 101 may include one or more nanosecond pulsers coupled together in a variety of ways.

[0050] In some embodiments, the nanosecond pulser stage 101 may include a DC power supply providing a constant DC voltage, which is switched by a switch 175 and provides switched power to a transformer 85. The DC power supply may include an offset power supply voltage 90 and an energy storage capacitor 66. If the transformer has a turns ratio of 1:10, then the transformer can generate 10kV on the load.

[0051] In some embodiments, if the load capacitance value (e.g., capacitance values ​​13 and 18) is smaller than the capacitance value of the energy storage capacitor 66, voltage doubling may (or may not) occur at the input of the transformer. For example, if the energy storage capacitor 66 provides 500V, then 1kV can be measured at the input of the transformer 85.

[0052] For example, switch 175 may include one or more solid-state switches, such as, for example, IGBTs, MOSFETs, silicon carbide MOSFETs, silicon carbide transistors, FETs, silicon carbide switches, gallium nitride switches, optoelectronic switches, etc. Switch 175 can be switched based on signals from a controller identified as Sig+ and Sig-.

[0053] In some embodiments, the nanosecond pulse phase 101 may include a buffer circuit, which may include any type of buffer circuit. In some embodiments, the buffer circuit may include a capacitor. In some embodiments, the buffer circuit may include a capacitor and a resistor. In some embodiments, the buffer circuit may include a capacitor, a resistor, and an inductor. In some embodiments, the buffer circuit may include a buffer resistor connected in parallel with a buffer diode, and a buffer capacitor 164. The buffer circuit may also include stray inductance. In some embodiments, the buffer resistor 161 and / or the buffer diode 163 may be placed between the collector of the switch 175 and the primary winding of the transformer 85. The buffer diode 163 may be used to suppress any overvoltage in the switch. The freewheeling diode 172 may also be coupled to the emitter side of the switch 65. Other different components not shown in the figures may be included. One or more switches or circuits may be configured in parallel or in series.

[0054] In some embodiments, switch 175 may switch so quickly that the voltage of the switch may never be at full voltage (e.g., the voltage of energy storage capacitor 66 and / or the voltage of offset supply voltage 90).

[0055] In some embodiments, the gate resistor coupled to switch 175 can be set using a short-time turn-on pulse.

[0056] In some embodiments, the nanosecond pulser stage 101 may include a freewheeling diode 172. In some embodiments, the freewheeling diode 172 may be used in conjunction with an inductive load to ensure that energy stored in the inductive load can be allowed to dissipate after the switch 175 is turned on in a manner that allows current to continue flowing through the inductor in the same direction and energy to dissipate in the resistive elements of the circuit. If the freewheeling diode 172 is not included, this can, for example, result in a large reverse voltage across the switch 175.

[0057] In some embodiments, the nanosecond pulser stage 101 may include a stray inductance 151 and / or a stray resistance 152. For example, the stray inductance 151 may be less than about 10 nH, 100 nH, 1,000 nH, 10,000 nH, etc. For example, the stray resistance 152 may be less than about 1 Ohm, 100 mOhm, 10 mOhm, etc.

[0058] In some embodiments, the energy recovery circuit 110 may be electrically coupled to the secondary side of the transformer and / or the energy storage capacitor 66. For example, the energy recovery circuit 110 may include a diode 130 (e.g., a crowbar diode) traversing the secondary side of the transformer 85. For example, the energy recovery circuit 110 may include an energy recovery diode 120 and an energy recovery inductor 115 (connected in series) that allow current to flow from the secondary side of the transformer 85 to charge the energy storage capacitor 66. The energy recovery diode 120 and the energy recovery inductor 115 may be electrically connected to the secondary side of the transformer 85 and the energy storage capacitor 66. In some embodiments, the energy recovery circuit 110 may include a diode 130 and / or an inductor 140 electrically coupled to the secondary side of the transformer 85. The inductor 140 may represent stray inductance and / or may include stray inductance of the transformer 85.

[0059] In some embodiments, the energy recovery inductor 115 may include any type of inductor, such as, for example, a ferrite core inductor or an air core inductor. In some embodiments, the energy recovery inductor 115 may have any type of geometry, such as, for example, a solenoid winding, a toroidal winding, etc. In some embodiments, the energy recovery inductor 115 may have an inductance value greater than approximately 10 μH, 50 μH, 100 μH, 500 μH, etc. In some embodiments, the energy recovery inductor 115 may have an inductance value from approximately 1 μH to approximately 100 mH.

[0060] In some embodiments, when the nanosecond pulser is on, current can charge the load phase 106 (e.g., charge capacitor 13, capacitor 12, or capacitor 18). For example, when the voltage on the secondary side of the transformer rises above the charge voltage on the energy storage capacitor 66, some current can flow through the energy recovery inductor 115. When the nanosecond pulser is off, current can flow from the capacitor (e.g., capacitor 52) within the load phase 106 through the energy recovery inductor 115 to charge the energy storage capacitor 66 until the voltage across the energy recovery inductor 115 is zero. Diode 130 prevents the capacitor within the load phase 106 from being fully charged along with the inductor within the load phase 106 or the DC bias circuit 104.

[0061] For example, the energy recovery diode 120 can prevent charge from flowing from the energy storage capacitor 66 to the capacitor within the load phase 106.

[0062] The value of the energy recovery inductor 115 can be selected to control the current drop time. In some embodiments, the energy recovery inductor 115 may have an inductance value between 1 μH and 600 H. In some embodiments, the energy recovery inductor 115 may have an inductance value greater than 50 H. In some embodiments, the energy recovery inductor 115 may have an inductance value less than approximately 50 μH, 100 μH, 150 μH, 200 μH, 250 μH, 300 μH, 350 μH, 350 μH, 400 μH, 400 μH, 500 μH, etc.

[0063] For example, if the energy storage capacitor 66 provides 500V, then 1kV is measured at the input of transformer 85 (e.g., due to voltage multiplication, as described above). When switch 175 is open, the 1kV at transformer 85 can be divided among the components of energy recovery circuit 110. If the values ​​are correctly selected (e.g., inductor 162 has a smaller inductance value than energy recovery inductor 115), the voltage across energy recovery diode 120 and energy recovery inductor 115 can be greater than 500V.

[0064] Current can then flow through the energy recovery diode 120 and / or charge the energy storage capacitor 66. Current can also flow through diode D3 and inductor 88. Once the energy storage capacitor 66 is charged, current may no longer flow through diode D3 and energy recovery inductor 115.

[0065] In some embodiments, the energy recovery circuit 110 can transfer energy (or charge) from the load phase 106 on, for example, fast timescales (e.g., 1 ns, 10 ns, 50 ns, 100 ns, 250 ns, 500 ns, 1,000 ns, etc.). The stray resistance value of the energy recovery circuit can be low to ensure that the pulses across the load phase 106 have a fast fall time tf. For example, the stray resistance of the energy recovery circuit 110 can have a resistance less than approximately 1 Ohm, 100 mOhm, 10 mOhm, etc. In some embodiments, the energy transfer efficiency from the load phase 106 can be high, for example, greater than approximately 60%, 70%, 80%, or 90%, etc.

[0066] It may or may not be necessary. Figure 1 Any number of components shown, such as, for example, diode 135 or diode 130 or inductor 140.

[0067] In some embodiments, the diode may be placed between the voltage source 65 and a connection point where the energy recovery circuit 110 is connected to the voltage source 65 and / or the energy storage capacitor 66. For example, this diode may be configured to allow current to flow from the voltage source 65 to the energy storage capacitor 66, but may not allow current to flow from the energy recovery circuit to the energy storage capacitor 66.

[0068] In some embodiments, the energy recovery circuit 110 may be removed. In some embodiments, a resistive output stage or a bias compensation circuit may be included. Many other circuits or circuit elements may be included.

[0069] In some embodiments, different load stages 106 may be used. In some embodiments, the load stage may include capacitively coupled plasma or inductively coupled plasma.

[0070] In some embodiments, the nanosecond pulser system 100 can output a waveform to the load stage 106. The waveform may include a plurality of high-voltage pulses and a sine wave between the high-voltage pulses. For example, the high-voltage pulses may have a pulse amplitude, pulse width, and pulse repetition frequency greater than approximately 2 kV. The sine wave may have a waveform frequency and a waveform amplitude greater than 100 V.

[0071] In some embodiments, the waveform frequency and / or waveform amplitude depend at least in part on one and / or both of the stray inductance and stray capacitance. For example, the stray inductance may depend substantially on the inductance value of inductor 87 and / or inductor 88. As another example, the inductance value of inductor 87 and / or inductor 88 may be between approximately 50 nH and approximately 1.8 μH. As another example, the inductance value of inductor 87 and / or inductor 88 may be between approximately 5 nH and approximately 20 μH. For example, the stray capacitance may depend substantially on the capacitance value of capacitor 52. For example, the capacitance value of capacitor 52 may be between approximately 250 pF and approximately 1.5 nF. As another example, the capacitance value of capacitor 52 may be between approximately 50 pF and approximately 20 nF.

[0072] The overall stray capacitance of the circuit can range from approximately 50 pF to approximately 20 nF. The overall stray inductance of the circuit can range from approximately 5 nH to approximately 20 μH.

[0073] In some embodiments, the waveform frequency and / or waveform amplitude depend at least in part on the pulse width.

[0074] Figure 2This is a circuit diagram of a nanosecond pulser system 200 having a resistive output stage 220 driving a load stage according to some embodiments. In this example, the energy recovery circuit 110 is removed from the nanosecond pulser system 100 and replaced by the resistive output stage 220.

[0075] The resistive output stage 220 may include any resistive output stage in the prior art. For example, the resistive output stage 220 may include any resistive output stage described in U.S. Patent Application No. US16 / 178,538, entitled “High Voltage Resistive Output Stage Circuit,” which is incorporated herein for all purposes.

[0076] For example, resistive output stage 220 may include inductor 37, resistor 50, and capacitor 19. In some embodiments, inductor 37 may include an inductance value of approximately 5 μH to approximately 25 μH. In some embodiments, resistor 50 may include a resistance value of approximately 50 ohms to approximately 250 ohms. In some embodiments, resistor 50 may include stray resistance in resistive output stage 220.

[0077] In some embodiments, resistor 50 may include a plurality of resistors connected in series or parallel. Capacitor 19 may represent the stray capacitance value of resistor 50, including the capacitance value set by the series and / or parallel resistors. For example, the capacitance value of stray capacitor 19 may be less than 500pF, 250pF, 100pF, 50pF, 10pF, 1pF, etc. For example, the capacitance value of stray capacitor 19 may be less than the load capacitance value, such as, for example, less than 12, 13, and / or 18.

[0078] In some embodiments, resistor 50 may discharge a load (e.g., a plasma shell capacitor). In some embodiments, resistive output phase 220 may be configured to discharge at an average power of approximately 1 kW per pulse cycle and / or at an energy of approximately 1 kW or less per pulse cycle in joules. In some embodiments, the resistance value of resistor 50 within resistive output phase 220 may be less than 200 ohms. In some embodiments, resistor 50 may comprise a plurality of series or parallel resistors having a total capacitance value of less than approximately 200 pF (e.g., 19).

[0079] In some embodiments, the resistive output stage 220 may include circuit elements that can be used to control the shape of the voltage waveform across the load. In some embodiments, the resistive output stage 220 may include only passive elements (e.g., resistors, capacitors, inductors, etc.). In some embodiments, the resistive output stage 220 may include active circuit elements (e.g., switches) and passive circuit elements. In some embodiments, for example, the resistive output stage 220 may be used to control the voltage rise time and / or the voltage fall time of the waveform.

[0080] In some embodiments, the resistive output stage 220 can discharge capacitive loads (e.g., wafers and / or plasma). For example, these capacitive loads may have small capacitance values ​​(e.g., 10pF, 100pF, 500pF, 1nF, 10nF, 100nF, etc.).

[0081] In some embodiments, the resistive output stage 220 can be used in a circuit with pulses having high pulse voltages (e.g., 1kV, 10kV, 20kV, 50kV, 100kV, etc.) and / or high frequencies (e.g., 1kHz, 10kHz, 100kHz, 200kHz, 500kHz, 1MHz, etc.) and / or frequencies of approximately 400kHz, 0.5MHz, 2.0MHz, 4.0MHz, 13.56MHz, 27.12MHz, 40.68MHz, 50MHz, etc.

[0082] In some embodiments, the resistive output stage 220 can be selected to handle high average power, high peak power, fast rise time and / or fast fall time. For example, the average power level may be greater than about 0.5kW, 1.0kW, 10kW, 25kW, etc., and / or the peak power level may be greater than about 1kW, 10kW, 100kW, 1MW, etc.

[0083] In some embodiments, the resistive output stage 220 may include a series or parallel network of passive components. For example, the resistive output stage 220 may include a series connection of a resistor, a capacitor, and an inductor. As another example, the resistive output stage 220 may include a capacitor in parallel with an inductor and a capacitor-inductor combination in series with a resistor. For example, 37 can be selected large enough that no significant energy is injected into the resistive output stage 220 when the rectifier has voltage. The values ​​of 50 and 50 can be selected so that the L / R time can deplete the appropriate capacitor in the load faster than the RF frequency.

[0084] Figure 3Three waveforms generated by a nanosecond pulser system 100 according to some embodiments are shown. Waveform 310 is measured at point 124 and waveform 315 is measured at point 122 (wafer waveform). Waveform 305 is the difference between the waveform measured at point 121 and the waveform measured at point 122. In this example, the wafer waveform has a frequency of approximately 19 MHz and a peak-to-peak amplitude of approximately 150 V. In this example, the pulse width is approximately 200 ns. And, the resulting ion current is approximately 1 amp.

[0085] The waveform frequency and / or waveform amplitude can depend on the values ​​of inductors 87, 88, 23, 12, and 13. For example, inductors 87 and / or 88 can have inductance values ​​less than approximately 500nH, 250nH, 100nH, 50nH, 25nH, etc. For these specific waveforms, inductors 87 and / or 88 can have an inductance value of approximately 50nH. Capacitor 23 can have a capacitance value less than approximately 1,000pF, 500pF, 250pF, 100pF, 50pF, etc. For these specific waveforms, capacitor 23 can have a capacitance value of approximately 250pF.

[0086] The capacitance values ​​of capacitors 12 and 13 may be fixed by load 106 or not, and may vary depending on the application. Capacitor 12 may have a capacitance value of approximately 6.4 nF and capacitor 13 may have a capacitance value of approximately 25 pF.

[0087] Figure 4 Three waveforms generated by a nanosecond pulser system 100 according to some embodiments are shown. Waveform 410 is measured at point 124 and waveform 415 is measured at point 122 (wafer waveform). Waveform 405 is the difference between the waveform measured at point 121 and the waveform measured at point 122. In this example, the wafer waveform has a frequency of approximately 19 MHz and a peak-to-peak amplitude of approximately 1.75 kV. The pulse width is approximately 350 ns. And, the resulting ion current is approximately 1 amp. Therefore, in this example, by changing the pulse width from 250 ns to 350 ns, the waveform amplitude is increased from 150 V to 1.75 kV.

[0088] The waveform frequency and / or waveform amplitude can depend on the values ​​of inductors 87, 88, 23, 12, and 13. For example, inductors 87 and / or 88 can have inductance values ​​less than approximately 500nH, 250nH, 100nH, 50nH, 25nH, etc. For these specific waveforms, inductors 87 and / or 88 can have an inductance value of approximately 50nH. Capacitor 23 can have a capacitance value less than approximately 1,000pF, 500pF, 250pF, 100pF, 50pF, etc. For these specific waveforms, capacitor 23 can have a capacitance value of approximately 250pF.

[0089] The capacitance values ​​of capacitors 12 and 13 may be fixed by load 106 or not, and may vary depending on the application. In this example, capacitor 12 may have a capacitance value of approximately 6.4 nF, and capacitor 13 may have a capacitance value of approximately 25 pF.

[0090] Figure 5 Three waveforms generated by a nanosecond pulser system 100 according to some embodiments are shown. Waveform 510 is measured at point 124 and waveform 515 is measured at point 122 (wafer waveform). Waveform 505 is the difference between the waveform measured at point 121 and the waveform measured at point 122. In this example, the wafer waveform has a frequency of approximately 19 MHz and a peak-to-peak amplitude of approximately 1.75 kV. The pulse width is approximately 1000 ns. And the ion current is approximately 1 amp.

[0091] The waveform frequency and / or waveform amplitude can depend on the values ​​of inductors 87, 88, 23, 12, and 13. For example, inductors 87 and / or 88 can have inductance values ​​less than approximately 500nH, 250nH, 100nH, 50nH, 25nH, etc. For these specific waveforms, inductors 87 and / or 88 can have an inductance value of approximately 50nH. Capacitor 23 can have a capacitance value less than approximately 1,000pF, 500pF, 250pF, 100pF, 50pF, etc. For these specific waveforms, capacitor 23 can have a capacitance value of approximately 250pF.

[0092] The capacitance values ​​of capacitors 12 and 13 may be fixed by load 106 or not, and may vary depending on the application. In this example, capacitor 12 may have a capacitance value of approximately 6.4 nF, and capacitor 13 may have a capacitance value of approximately 25 pF.

[0093] Therefore, in this example, by changing the pulse width from 350ns to 1000ns, the waveform amplitude reaches the limit (around 400ns) and does not significantly increase the peak-to-peak amplitude of the waveform.

[0094] Figure 6 Three waveforms generated by a nanosecond pulser system 100 according to some embodiments are shown. Waveform 610 is measured at point 124 and waveform 615 is measured at point 122 (wafer waveform). Waveform 605 is the difference between the waveform measured at point 121 and the waveform measured at point 122. In this example, the wafer waveform has a frequency of approximately 5.0 MHz and a peak-to-peak amplitude of approximately 764 V. The pulse width is approximately 200 ns. And, the resulting ion current is approximately 1 amp.

[0095] The waveform frequency and / or waveform amplitude can depend on the values ​​of inductors 87, 88, 23, 12, and 13. For example, inductors 87 and / or 88 can have inductance values ​​less than approximately 500nH, 250nH, 100nH, 50nH, 25nH, etc. For these specific waveforms, inductors 87 and / or 88 can have an inductance value of approximately 400nH. Similarly, capacitor 23 can have a capacitance value less than approximately 10nF, 5nF, 1nF, 500pF, 250pF, 100pF, 50pF, etc. For these specific waveforms, capacitor 23 can have a capacitance value of approximately 1nF.

[0096] The capacitance values ​​of capacitors 12 and 13 may be fixed by load 106 or not, and may vary depending on the application. In this example, capacitor 12 may have a capacitance value of approximately 6.4 nF, and capacitor 13 may have a capacitance value of approximately 1 nF.

[0097] Therefore, in this example, by increasing the inductance of inductor 87, the inductance of inductor 88, and the capacitance of capacitor C8, and decreasing the capacitance of capacitor 13, the waveform frequency is reduced to approximately 5.0 MHz. Additionally, in this example, a pulse width below approximately 250 ns (e.g., 197 ns) does not produce the same large waveform amplitude.

[0098] Figure 7Three waveforms generated by a nanosecond pulser system 100 according to some embodiments are shown. Waveform 710 is measured at point 124 and waveform 715 is measured at point 122 (wafer waveform). Waveform 705 is the difference between the waveform measured at point 121 and the waveform measured at point 122. In this example, the wafer waveform has a frequency of approximately 5.0 MHz and a peak-to-peak amplitude of approximately 2.5 kV. The pulse width is approximately 350 ns. And the resulting ion current is approximately 1 amp.

[0099] The waveform frequency and / or waveform amplitude can depend on the values ​​of inductors 87, 88, 23, 12, and 13. For example, inductors 87 and / or 88 can have inductance values ​​less than approximately 400nH, 250nH, 100nH, 50nH, 25nH, etc. For these specific waveforms, inductors 87 and / or 88 can have an inductance value of approximately 400nH. Similarly, capacitor 23 can have capacitance values ​​less than approximately 10nF, 5nF, 1nF, 500pF, 250pF, 100pF, 50pF, etc. For these specific waveforms, capacitor 23 can have a capacitance value of approximately 1nF.

[0100] The capacitance values ​​of capacitors 12 and 13 may be fixed by load 106 or not, and may vary depending on the application. In this example, capacitor 12 may have a capacitance value of approximately 6.4 nF, and capacitor 13 may have a capacitance value of approximately 1 nF.

[0101] Therefore, in this example, by increasing the inductance values ​​of inductor 87 and inductor 88, although the waveform amplitude is reduced, the pulse amplitude is decreased.

[0102] Figure 8 Three waveforms generated by a nanosecond pulser system 100 according to some embodiments are shown. Waveform 810 is measured at point 124 and waveform 815 is measured at point 122 (wafer waveform). Waveform 805 is the difference between the waveform measured at point 121 and the waveform measured at point 122. In this example, the wafer waveform has a frequency of approximately 2.0 MHz and a peak-to-peak amplitude of approximately 4.78 kV. The pulse width is approximately 350 ns. And the resulting ion current is approximately 1 amp.

[0103] The waveform frequency and / or waveform amplitude can depend on the values ​​of inductors 87, 88, 23, 12, and 13. For example, inductors 87 and / or 88 can have inductance values ​​less than approximately 2,000 nH, 1,500 nH, 1,000 nH, 500 nH, 100 nH, 50 nH, 25 nH, etc. For these specific waveforms, inductors 87 and / or 88 can have an inductance value of approximately 1800 nH. For example, capacitor 23 can have a capacitance value less than approximately 10 nF, 5 nF, 1 nF, 500 pF, 250 pF, 100 pF, 50 pF, etc. For these specific waveforms, capacitor 23 can have a capacitance value of approximately 1.5 nF.

[0104] The capacitance values ​​of capacitors 12 and 13 may be fixed by load 106 or not, and may vary depending on the application. In this example, capacitor 12 may have a capacitance value of approximately 6.4 nF, and capacitor 13 may have a capacitance value of approximately 100 pF.

[0105] Therefore, in this example, by increasing the inductance values ​​of inductor 87 and inductor 88, although the waveform amplitude is reduced, the pulse amplitude is decreased.

[0106] Unless otherwise stated, the term "substantially" means within 5% or 10% of the value involved or within manufacturing tolerances. Unless otherwise stated, the term "approximately" means within 5% or 10% of the value involved or within manufacturing tolerances.

[0107] The conjunction "or" is open.

[0108] The terms “first,” “second,” “third,” etc., are used to distinguish the corresponding elements and are not used to identify a specific order of these elements unless otherwise stated or explicitly stated or required.

[0109] Numerous specific details are provided to provide a comprehensive understanding of the subject matter claimed in the claims. However, those skilled in the art will understand that the subject matter claimed in the claims can be practiced without these specific details. In other instances, methods, apparatus, or systems that should be known to those skilled in the art are not described in detail to avoid obscuring the subject matter claimed in the claims.

[0110] The system or the system under discussion is not limited to any particular hardware architecture or configuration. A computing device may include any suitable arrangement of components that can provide results under one or more conditional inputs. Suitable computing devices include multi-purpose microprocessor-based computer systems that acquire stored software that programs or configures a general-purpose computing device as a dedicated computing device for implementing one or more embodiments of this subject matter. Any suitable program, script, or other type of language or mixture of languages ​​can be used to implement the viewpoints in the software for use in programming or configuring the computing device.

[0111] Although the subject matter has been described in detail by way of specific embodiments, those skilled in the art will readily make changes, variations, and equivalent features to these embodiments upon understanding the foregoing. Accordingly, it is understood that the content described herein is for illustrative purposes and not for limitation, and does not exclude the inclusion of such modifications, variations, and / or additions that would be readily apparent to those skilled in the art.

Claims

1. Power supply, including: High-voltage power supply; A nanosecond pulse generator, which is electrically coupled to the high-voltage power supply, and which switches the voltage from the high-voltage power supply at a high frequency; A transformer having a primary side and a secondary side, wherein the nanosecond pulse generator is electrically coupled to the primary side of the transformer; and The output, electrically coupled to the transformer, generates a waveform, the waveform including: Multiple high-voltage pulses, wherein the high-voltage pulses have a pulse amplitude, pulse width, and pulse repetition frequency greater than 2kV; and A sinusoidal waveform having a waveform frequency and a waveform amplitude greater than 100V, wherein the waveform amplitude is less than the pulse amplitude; and wherein the pulse repetition frequency is less than the waveform frequency.

2. The power supply according to claim 1, further comprising an energy recovery circuit electrically coupled to the secondary side of the transformer, the energy recovery circuit comprising: An energy recovery inductor electrically coupled to the high-voltage power supply; A crowbar diode, wherein the crowbar diode is configured to be connected in parallel with the secondary side of the transformer; A second diode is configured to be connected in series with the energy recovery inductor and to direct current from the load through the energy recovery inductor to the high-voltage power supply.

3. The power supply according to claim 1, wherein, The waveform frequency is greater than 10MHz.

4. The power supply according to claim 1, wherein, The power supply includes stray inductance and stray capacitance, wherein the waveform frequency and / or the waveform amplitude are at least partially dependent on one and / or both of the stray inductance and the stray capacitance.

5. The power supply according to claim 1, wherein, The waveform frequency and / or the waveform amplitude depend at least in part on the pulse width.

6. The power supply according to claim 1, wherein, The power supply includes a stray inductor with an inductance value of less than 1.8 μH.

7. The power supply according to claim 1, wherein, The power supply includes a stray inductor with an inductance value of less than 400nH.

8. The power supply according to claim 1, wherein, The power supply includes stray capacitors with a capacitance value of less than 20nF.

9. The power supply according to claim 1, wherein, The output is coupled to a plasma chamber, wherein the sinusoidal waveform generates plasma within the plasma chamber and the plurality of high-voltage pulses accelerate plasma particles within the plasma chamber.

10. The power supply according to claim 1, wherein, The pulse amplitude is greater than 5kV, and each of the plurality of high-voltage pulses has a pulse rise time of less than 20ns.

11. Power supply, including: High-voltage power supply; A nanosecond pulse generator, which is electrically coupled to the high-voltage power supply, and which switches the voltage from the high-voltage power supply at a high frequency; A transformer having a primary side and a secondary side, wherein the nanosecond pulse generator is electrically coupled to the primary side of the transformer; The output, electrically coupled to the transformer, generates a waveform, the waveform including: Multiple high-voltage pulses, each high-voltage pulse having a pulse amplitude, a pulse width, and a pulse repetition frequency; and A sinusoidal waveform with both frequency and amplitude: Stray capacitance, the stray capacitance having a capacitance value of less than 20nF as measured from the output; and A stray inductor having an inductance value of less than 400 nH as measured from the output.

12. The power supply according to claim 11, wherein, The waveform frequency and / or the waveform amplitude depend at least in part on one and / or both of the stray inductance and the stray capacitance.

13. The power supply according to claim 11, wherein, The waveform frequency and / or the waveform amplitude depend at least in part on the pulse width.

14. The power supply according to claim 11, wherein, The pulse amplitude is greater than 5kV, and each of the plurality of high-voltage pulses has a pulse rise time of less than 20ns.

15. The power supply according to claim 11, wherein, The waveform amplitude is less than the pulse amplitude.

16. The power supply according to claim 11, wherein, The pulse repetition frequency is less than the waveform frequency.

17. The power supply according to claim 11, wherein, The waveform frequency is between 2MHz and 20MHz.

18. The power supply of claim 11, further comprising an energy recovery circuit electrically coupled to the secondary side of the transformer, the energy recovery circuit comprising: An energy recovery inductor electrically coupled to the high-voltage power supply; A crowbar diode, wherein the crowbar diode is configured to be connected in parallel with the secondary side of the transformer; and A second diode is configured to be connected in series with the energy recovery inductor and to direct current from the load through the energy recovery inductor to the high-voltage power supply.

19. A semiconductor plasma system, comprising: Plasma chamber; and High-voltage power supply, the high-voltage power supply comprising: High-voltage power supply; A nanosecond pulse generator, which is electrically coupled to the high-voltage power supply, and which switches the voltage from the high-voltage power supply at a high frequency; A transformer having a primary side and a secondary side, wherein the nanosecond pulse generator is electrically coupled to the primary side of the transformer; and The output is electrically coupled to the transformer and the plasma chamber, and generates a waveform within the plasma chamber, the waveform including: A sinusoidal waveform configured to generate plasma within the plasma chamber, the sinusoidal waveform having a waveform frequency and a waveform amplitude greater than 100V; and Multiple high-voltage pulses accelerate plasma particles within the plasma chamber, the high-voltage pulses having a pulse amplitude, pulse width, and pulse repetition frequency greater than 2 kV.

20. The semiconductor plasma system according to claim 19, wherein, The power supply has stray capacitance and / or stray inductance, wherein the waveform frequency and / or the waveform amplitude are at least partially dependent on one and / or both of the stray inductance and the stray capacitance.

21. The semiconductor plasma system according to claim 19, wherein, The waveform frequency and / or the waveform amplitude depend at least in part on the pulse width.

22. The semiconductor plasma system according to claim 19, wherein, The plasma chamber generates a plasma shell with shell capacitance, wherein the waveform frequency and / or the waveform amplitude depend on the shell capacitance.

23. The semiconductor plasma system according to claim 19, wherein, The power supply includes a stray inductor with an inductance value of less than 400nH.

24. The semiconductor plasma system according to claim 19, wherein, The power supply includes stray capacitors with a capacitance value of less than 20nF.

25. The semiconductor plasma system according to claim 19, wherein, The amplitude of the pulse is greater than 5kV, and each of the plurality of high-voltage pulses has a pulse rise time of less than 40ns.

26. The semiconductor plasma system according to claim 19, wherein, The waveform amplitude is less than the pulse amplitude.

27. The semiconductor plasma system according to claim 19, wherein, The pulse repetition frequency is less than the waveform frequency.

28. The semiconductor plasma system according to claim 19, wherein, The waveform frequency is greater than 10MHz.

29. The semiconductor plasma system according to claim 19, wherein, The power supply further includes an energy recovery circuit electrically coupled to the secondary side of the transformer, the energy recovery circuit comprising: An energy recovery inductor electrically coupled to the high-voltage power supply; A crowbar diode, wherein the crowbar diode is configured to be connected in parallel with the secondary side of the transformer; and A second diode is configured to be connected in series with the energy recovery inductor and to direct current from the load through the energy recovery inductor to the high-voltage power supply.

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