Abstract: In one embodiment, an RF impedance matching network utilizing at least one electronically variable capacitors (EVC) is disclosed. Each EVC includes discrete capacitors operably coupled in parallel, the discrete capacitors including fine capacitors and coarse capacitors. A control circuit determines a parameter related to the plasma chamber and, based on the parameter, determines which of the coarse capacitors and which of the fine capacitors to have switched in to cause an impedance match. The increase of the variable total capacitance of each EVC is achieved by switching in more of the coarse capacitors or more of the fine capacitors than are already switched in without switching out a coarse capacitor that is already switched in.

Abstract: In one embodiment, a switching circuit includes an electronic switch comprising one or more diodes for switching a reactance element within an electronically variable reactance element. A first power switch receives an input signal and a first voltage, and switchably connects the first voltage to a common output in response to the received input signal. A second power switch receives an input signal and a second voltage, and switchably connects the second voltage to the common output in response to the received input signal. The second voltage is opposite in polarity to the first voltage. The first power switch and the second power switch asynchronously connect the first voltage and the second voltage, respectively, to the common output, the one or more diodes of the electronic switch being switched according to the first voltage or the second voltage being connected to the common output.

Abstract: In one embodiment, a method of matching an impedance is disclosed. An impedance matching network is coupled between a radio frequency (RF) source and a plasma chamber. The matching network includes a variable reactance element (VRE) having different positions for providing different reactances. The RF source has an RF source control circuit carrying out a power control scheme to control a power delivered to the matching network. Based on a determined parameter, a new position for the VRE is determined to reduce a reflected power at the RF input of the matching network. The matching network provides a notice signal to the RF source indicating the VRE will be altered. In response to the notice signal, the RF source control circuit alters the power control scheme. While the power control scheme is altered, the VRE is altered to the new position.

Abstract: In one embodiment, an RF impedance matching network is disclosed. The matching network is coupled between an RF source having a variable frequency and a plasma chamber having a variable chamber impedance. The matching network includes a variable reactance element (VRE), and a control circuit coupled to the VRE and a sensor, the sensor configured to detect an RF parameter. To cause an impedance match between the RF source and the plasma chamber, the control circuit determines, based on the detected RF parameter and a VRE configuration, a new source frequency for the RF source. The impedance match then causes the variable frequency of the RF source to alter to the new source frequency.

Abstract: In one embodiment, the present disclosure is directed to a method for performing diagnostics on a matching network that utilizes an electronically variable capacitor (EVC). According to the method, all the discrete capacitors of the EVC are switched out. At a first node, a parameter associated with a current flowing between a power supply and one or more of the switches of the discrete capacitors is measured. The method then switches in, one at a time, each discrete capacitor of the EVC. Upon the switching in of each discrete capacitor, the method remeasures the parameter at the first node and determines whether a change to the parameter at the first node is within a predetermined range to determine whether the corresponding switch, driver circuit, or filter of the discrete capacitor most recently switch in has failed.

Abstract: In one embodiment, the present disclosure is directed to a method of impedance matching where an RF source is providing at least two non-zero pulse levels. For each of the at least two pulse levels, at a regular time interval, a control unit determines a parameter-related value that is based on a parameter related to the load, and repeatedly detects which of the at least two non-zero pulse levels is being provided by the RF source. Upon detecting one of the at least two non-zero pulse levels, for the detected pulse level, the control unit measures the parameter related to the load to determine a measured parameter value, determines the parameter-related value based on the measured parameter value, and alters the at least one EVC to provide the match configuration, the match configuration based on the parameter-related value.

Abstract: In one embodiment, the present disclosure may be directed to an impedance matching network that includes an electronically variable capacitor (EVC). The EVC includes discrete capacitors and corresponding switches, each switch configured to switch in and out one of the discrete capacitors to alter a capacitance of the EVC. The switches are operably coupled to a power supply providing a blocking voltage to the switches. A control circuit determines a blocking voltage value of the power supply. Upon determining the blocking voltage value is at or below a predetermined first level, the control circuit causes a limited altering of the capacitance of the EVC, the limited altering limiting the number or type of discrete capacitors to switch in or out based on the extent to which the blocking voltage value is at or below the first level.

Abstract: In one embodiment, an RF impedance matching network for a plasma chamber is disclosed. The matching network includes a mechanically variable capacitor (MVC) and a second variable capacitor. A control circuit is configured to carry out a first process for altering the second variable capacitor and the RF source frequency to reduce reflected power. The control circuit is further configured to carry out a second process of, upon determining that the alteration of the RF source frequency has caused the RF source frequency to be outside, at a minimum, or at a maximum of a predetermined frequency range, determining a new MVC configuration to cause the RF source frequency, according to the first process, to be altered to be within or closer to the predetermined frequency range. The new MVC configuration is based on the RF source frequency and the predetermined frequency range.

Abstract: In one embodiment, a switching circuit includes an electronic switch comprising one or more diodes for switching a reactance element within an electronically variable reactance element. A first power switch receives an input signal and a first voltage, and switchably connects the first voltage to a common output in response to the received input signal. A second power switch receives an input signal and a second voltage, and switchably connects the second voltage to the common output in response to the received input signal. The second voltage is opposite in polarity to the first voltage. The first power switch and the second power switch asynchronously connect the first voltage and the second voltage, respectively, to the common output, the one or more diodes of the electronic switch being switched according to the first voltage or the second voltage being connected to the common output.

Abstract: In one embodiment, a method of using an impedance matching network to determine a plasma chamber characteristic is disclosed. An impedance matching network is coupled between a radio frequency (RF) source and a plasma chamber. The matching network includes a variable reactance element (VRE) having different positions for providing different reactances. A characteristic of the plasma chamber is determined based on reference values for a parameter of the matching network and a current value. Based thereon, either a visual or audible indication of the determined characteristic of the plasma chamber is provided, or an action is taken to address the determined characteristic.

Abstract: In one embodiment, a method, a method of manufacturing a semiconductor is disclosed. A monitored semiconductor manufacturing system (monitored system) is operated over a period of time, the monitored system comprising an impedance matching network coupled between a radio frequency (RF) source and a plasma chamber. First values for a parameter of the monitored system are received, the first values comprising different values for the parameter over the time period of operation of the monitored system, and a learning model is trained using the first values for the parameter. A substrate is then placed in a plasma chamber of a controlled semiconductor manufacturing system (controlled system). A characteristic of the controlled system is determined using a current value of the parameter and the trained learning model. An action is then taken upon the controlled system to address the determined characteristic.

Abstract: In one embodiment, a method of impedance matching and controlling the power delivered to a plasma chamber is disclosed. A matching network includes a variable reactance element (VRE), the VRE having different positions for providing different reactances. Based on a determined parameter, the method determines potential new positions for the VRE that would have a threshold effectiveness in providing an impedance match between the RF source and the plasma chamber. A preferred position for the VRE is determined by determining the one of the potential new positions meeting the threshold effectiveness whose efficiency in delivering RF power from the RF input to the RF output would cause an RF power at the RF output to be closest to a desired RF power.

Abstract: In one embodiment, a method of matching an impedance is disclosed. A matching network includes an electronically variable reactance element (EVRE) comprising discrete reactance elements and corresponding switches. For a determined parameter, potential new positions for the EVRE are determined, the potential new positions having differing effectiveness in causing an impedance match between an RF source and a plasma chamber. The discrete reactance elements of the EVRE that are currently restricted from switching are determined. A preferred position for the EVRE is determined as being the one of the potential new positions that provides greatest effectiveness in providing an impedance match while also not requiring switching in or out of any of the discrete reactance elements that are currently restricted from switching.

Abstract: In one embodiment, the present disclosure may be directed to an impedance matching network that includes an electronically variable capacitor (EVC). The EVC includes discrete capacitors and corresponding switches, each switch configured to switch in and out one of the discrete capacitors to alter a capacitance of the EVC. The switches are operably coupled to a power supply providing a blocking voltage to the switches. A control circuit determines a blocking voltage value of the power supply. Upon determining the blocking voltage value is at or below a predetermined first level, the control circuit causes a limited altering of the capacitance of the EVC, the limited altering limiting the number or type of discrete capacitors to switch in or out based on the extent to which the blocking voltage value is at or below the first level.

Abstract: In one embodiment, an RF impedance matching network utilizing at least one electronically variable capacitors (EVC) is disclosed. Each EVC includes discrete capacitors operably coupled in parallel, the discrete capacitors including fine capacitors and coarse capacitors. A control circuit determines a parameter related to the plasma chamber and, based on the parameter, determines which of the coarse capacitors and which of the fine capacitors to have switched in to cause an impedance match. The increase of the variable total capacitance of each EVC is achieved by switching in more of the coarse capacitors or more of the fine capacitors than are already switched in without switching out a coarse capacitor that is already switched in.

Abstract: In one embodiment, the present disclosure is directed to an RF impedance matching network that includes an RF input coupled to an RF source, an RF output coupled to a plasma chamber, and an electronically variable capacitor (EVC). A first control circuit controls the EVC and is separate and distinct from a second control circuit controlling the RF source. To assist in causing an impedance match between the RF source and the plasma chamber, the first control circuit determines, using a match lookup table with a value based on a detected RF parameter, a new EVC configuration for providing a new EVC capacitance. To further cause the impedance match, the second control circuit alters the variable frequency of the RF source, but operates independently from the first control circuit.

Abstract: In one embodiment, an RF impedance matching circuit is disclosed. The matching circuit is coupled between a plasma chamber and an RF source providing an RF signal having a frequency. The matching circuit includes a first electronically variable capacitor having a first variable capacitance and a second electronically variable capacitor having a second variable capacitance. A control circuit determines a first parameter related to the plasma chamber, and then determines, based on the first parameter, a first capacitance value for the first electronically variable capacitor and a second capacitance value for the second electronically variable capacitor. The control circuit then generates a control signal to alter the first variable capacitance and the second variable capacitance accordingly, causing the RF power reflected back to the RF source to decrease while the frequency of the RF source is not altered.

Abstract: In one embodiment, an RF impedance matching network for a plasma chamber is disclosed. It includes a variable capacitor comprising a plurality of capacitors comprising first coarse capacitors each having a substantially similar first coarse capacitance, second coarse capacitors each having a substantially similar second coarse capacitance, and fine capacitors having different capacitances that increase in value. At least one of the fine capacitors has a capacitance greater than the first coarse capacitance. A control circuit is configured cause a gradual increase in the total capacitance of the variable capacitor by switching in, in a predetermined order, each of the first coarse capacitors, followed by each of the second coarse capacitors, only switching in the fine capacitors whose capacitance is less than a capacitance of a next coarse capacitor of the coarse capacitors predetermined to be switched in next.

Abstract: In one embodiment, the present disclosure is directed to a method for performing diagnostics on a matching network that utilizes an electronically variable capacitor (EVC). According to the method, all the discrete capacitors of the EVC are switched out. At a first node, a parameter associated with a current flowing between a power supply and one or more of the switches of the discrete capacitors is measured. The method then switches in, one at a time, each discrete capacitor of the EVC. Upon the switching in of each discrete capacitor, the method re-measures the parameter at the first node and determines whether a change to the parameter at the first node is within a predetermined range to determine whether the corresponding switch, driver circuit, or filter of the discrete capacitor most recently switch in has failed.

Abstract: In one embodiment, an RF impedance matching network for a plasma chamber is disclosed. The matching network includes a mechanically variable capacitor (MVC) and a second variable capacitor. A control circuit is configured to carry out a first process for altering the second variable capacitor and the RF source frequency to reduce reflected power. The control circuit is further configured to carry out a second process of, upon determining that the alteration of the RF source frequency has caused the RF source frequency to be outside, at a minimum, or at a maximum of a predetermined frequency range, determining a new MVC configuration to cause the RF source frequency, according to the first process, to be altered to be within or closer to the predetermined frequency range. The new MVC configuration is based on the RF source frequency and the predetermined frequency range.