Non-contact measurement system and method for coil resistivity of ion implanter

Abstract

The invention discloses a non-contact measurement system and method for the coil resistivity of an ion implanter. The system comprises a control unit, a magnetic field detection unit and an induction coil unit, the control unit is respectively connected with the magnetic field detection unit, the induction coil unit and the coil to be detected; the magnetic field detection unit is used for detecting a magnetic field signal generated by the coil to be detected and sending the magnetic field signal to the control unit; the induction coil unit is used for generating induced electromotive force corresponding to a coil to be detected and sending the induced electromotive force to the control unit; the control unit is used for receiving the magnetic field signal of the magnetic field detection unit and the induced electromotive force of the induction coil unit so as to calculate the coil resistivity. The method has the advantages of accurate measurement and the like.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of semiconductor equipment, and in particular to a non-contact measurement system and method for the resistivity of a coil of an ion implanter. Background Art

[0002] In modern semiconductor device manufacturing, precise control of coil resistivity is crucial to ensure uniformity of the ion implantation process. Existing direct contact resistivity measurements are usually performed with the aid of four-terminal electrodes. When the coil is quite small or the resistivity is very high, a large error will occur, that is, the resistivity will be significantly higher than the actual value. On the other hand, the surface of the coil is easily corroded and polluted by the environment in the industrial field, and oxides will form on the surface of the sample to be tested, making it difficult to make good contact with the coil. Summary of the invention

[0003] In view of the technical problems existing in the prior art, the present invention provides a non-contact measurement system and method for accurately measuring the resistivity of an ion implanter coil.

[0004] In order to solve the above technical problems, the technical solution proposed by the present invention is:

[0005] A non-contact measurement system for the resistivity of an ion implanter coil comprises a control unit, a magnetic field detection unit and an induction coil unit; the control unit is respectively connected to the magnetic field detection unit, the induction coil unit and the coil to be measured;

[0006] The magnetic field detection unit is used to detect the magnetic field signal generated by the coil to be tested and send it to the control unit;

[0007] The induction coil unit is used to generate an induced electromotive force corresponding to the coil to be tested, and send it to the control unit;

[0008] The control unit is used to receive the magnetic field signal of the magnetic field detection unit and the induced electromotive force of the induction coil unit to calculate the coil resistivity.

[0009] Preferably, the magnetic field detection unit includes a giant magnetoresistance sensor and a fluxgate sensor.

[0010] Preferably, the induction coil unit comprises a first induction coil and a second induction coil, and the first induction coil and the second induction coil are respectively located at two ends of the coil to be measured.

[0011] Preferably, the control unit comprises a signal processing unit, a digital signal processor, a display control unit and a data processing unit; the signal processing unit, the digital signal processor, the display control unit and the data processing unit are connected in sequence.

[0012] The present invention also discloses a measurement method of a non-contact measurement system for the resistivity of an ion implanter coil, comprising the steps of:

[0013] The magnetic field detection unit detects the magnetic field signal generated by the coil to be tested and sends it to the control unit;

[0014] The induction coil unit generates an induced electromotive force corresponding to the coil to be tested, and sends it to the control unit;

[0015] The control unit receives the magnetic field signal of the magnetic field detection unit to calculate the first coil resistivity, calculates the second coil resistivity according to the induced electromotive force of the induction coil unit; and then obtains the final coil resistivity according to the first coil resistivity and the second coil resistivity.

[0016] Preferably, the direction and magnitude of the magnetic field are detected respectively by a giant magnetoresistance sensor and a fluxgate sensor, and the two detection results are fused by a vector analysis method to obtain the first coil resistivity.

[0017] Preferably, the corresponding relationship between the magnetic field strength and the coil resistivity is obtained as follows:

[0018]

[0019] Where S represents the cross-sectional area of ​​the coil, E represents the induced electromotive force, L represents the length of the coil, Itrue represents the monitored coil current value, and Iset represents the preset current; ρ 真 is the resistivity corresponding to I true, ρ 设定 Set the corresponding resistivity for I; Δρ is ρ 真 and ρ 设定 The difference between .

[0020] Preferably, the process of obtaining the resistivity of the second coil is:

[0021] Obtaining the induced electromotive force of the first induction coil and the induced electromotive force of the second induction coil;

[0022] The phase difference is obtained based on the induced electromotive force of the first induction coil and the induced electromotive force of the second induction coil. Amplitude value A1, phase difference Amplitude value A2; where phase difference represents the difference between the induced electromotive force generated by the first magnetic coil on the first induction coil and the induced electromotive force generated on the second induction coil; the amplitude value A1 is the amplitude value ratio of the induced electromotive force generated by the first magnetic coil on the first induction coil and the induced electromotive force generated on the second induction coil; the phase difference represents the difference between the induced electromotive force generated by the second magnetic coil on the first induction coil and the induced electromotive force generated on the second induction coil; the amplitude value A2 is the amplitude value ratio of the induced electromotive force generated by the second magnetic coil on the first induction coil and the induced electromotive force generated on the second induction coil;

[0023] According to the phase difference Amplitude value A1, phase difference Amplitude value A2 results in the resistivity of the second electrical coil.

[0024] Preferably, according to the phase difference Amplitude value A1, phase difference The amplitude value A2 obtains the angle corresponding to the current value at the current moment and amplitude value A3, through The second resistivity ρ2 is calculated by A3.

[0025] Preferably, the final coil resistivity ρ is obtained according to the first coil resistivity ρ1 and the second coil resistivity ρ2, wherein ρ=(ρ1+ρ2) / 2.

[0026] Compared with the existing technology,

[0027] The present invention realizes non-contact monitoring of coil resistivity and enhances measurement accuracy by combining advanced giant magnetoresistance sensors and fluxgate sensors; ensures the accuracy of the corresponding relationship between set current and resistivity through efficient signal processing technology; and provides a more comprehensive and reliable analysis strategy for actual experimental operations in actual experiments by taking into account changes in the magnetic field. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a diagram showing an embodiment of the magnetic field detection unit in the present invention during specific application.

[0029] Figure 2 This is a diagram showing an embodiment of the induction coil unit in the present invention during specific application.

[0030] Figure 3 The flowchart of the second coil resistivity measuring method in an embodiment of the present invention.

[0031] Figure 4 Schematic diagram of the angle of the induction coil in the present invention.

[0032] Legend: 1. Magnetic field detection unit; 101. Giant magnetoresistance sensor; 102. Fluxgate sensor; 2. Magnet coil; 201. First magnet coil; 202. Second magnet coil; 3. Induction coil unit; 301. First induction coil; 302. Second induction coil; 4. Signal processing unit; 401. Low noise amplifier; 402. Bandpass filter; 5. Digital signal processor; 6. Display control unit; 7. Data processing unit; 8. Host computer. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0034] like Figure 1 and Figure 2 As shown, the non-contact measurement system of the coil resistivity of the ion implanter according to the embodiment of the present invention comprises a control unit, a magnetic field detection unit and an induction coil unit; the control unit is respectively connected to the magnetic field detection unit, the induction coil unit and the coil to be measured;

[0035] The magnetic field detection unit is used to detect the magnetic field signal generated by the coil to be tested and send it to the control unit;

[0036] The induction coil unit is used to generate an induced electromotive force corresponding to the coil to be tested and send it to the control unit;

[0037] The control unit is used to receive the magnetic field signal of the magnetic field detection unit and the induced electromotive force of the induction coil unit to calculate the coil resistivity.

[0038] like Figure 1 As shown, the magnetic field detection unit includes a giant magnetoresistance sensor and a fluxgate sensor. The giant magnetoresistance sensor and the fluxgate sensor have high sensitivity and accuracy characteristics and are suitable for magnetic field monitoring in complex electrical environments. Specifically, the giant magnetoresistance sensor and the fluxgate sensor are used to jointly monitor the magnetic field changes to accurately measure the resistivity of the magnet coil in the high-energy ion implanter.

[0039] like Figure 2 As shown, the induction coil unit includes a first induction coil and a second induction coil, and the first induction coil and the second induction coil are respectively located at two ends of the coil to be tested.

[0040] The present invention uses innovative non-contact measurement technology to accurately measure coil resistivity in high frequency and complex environments, thereby optimizing the performance of ion implanters and the quality of semiconductor equipment.

[0041] like Figure 3 As shown, the embodiment of the present invention also discloses a measurement method of a non-contact measurement system for the resistivity of an ion implanter coil as described above, comprising the steps of:

[0042] The magnetic field detection unit detects the magnetic field signal generated by the coil to be tested and sends it to the control unit;

[0043] The induction coil unit generates an induced electromotive force corresponding to the coil to be measured and sends it to the control unit;

[0044] The control unit receives the magnetic field signal of the magnetic field detection unit and the induced electromotive force of the induction coil unit to calculate the coil resistivity.

[0045] Specifically, a giant magnetoresistance sensor and a fluxgate sensor are used to jointly monitor the change of the magnetic field to accurately measure the resistivity ρ1 of the first coil of the magnet coil in the high-energy ion implanter. The signal processing unit and digital signal processor in the control unit are used to optimize the processing of the captured signal and improve the accuracy and reliability of the data; and to display the measured data in real time and record the relationship between the change in the resistivity of the first coil and the change in the current as well as the historical data to support long-term trend analysis and equipment maintenance;

[0046] Then, by obtaining the magnetic moments m1 and m2 of the first induction coil and the second induction coil, the phase difference is calculated. Amplitude ratio A1, phase difference Amplitude ratio A2, thus the phase difference and amplitude ratio A3, according to and A3 to obtain the second coil resistivity ρ2;

[0047] Finally, the final resistivity ρ of the magnet coil is obtained by combining the first coil resistivity ρ1 and the second coil resistivity ρ2.

[0048] The present invention realizes non-contact monitoring of coil resistivity and enhances measurement accuracy by combining advanced giant magnetoresistance sensors and fluxgate sensors; ensures the accuracy of the corresponding relationship between set current and resistivity through efficient signal processing technology; and provides a more comprehensive and reliable analysis strategy for actual experimental operations in actual experiments by taking into account changes in the magnetic field.

[0049] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0050] The size and direction of the magnetic field are important reference factors for contactless resistivity measurement. The giant magnetoresistance sensor is very sensitive to changes in the magnetic field and can measure smaller changes in the magnetic field. The relationship between the output of the sensor and the magnetic field has a wide linear range. The fluxgate sensor can monitor small changes in the magnetic field and the direction of the magnetic field, but in a strong magnetic field environment, the sensor will be disturbed by the outside world and lose system stability and sensitivity. In the present invention, the giant magnetoresistance sensor and the fluxgate sensor can monitor small changes in the magnetic field. The data monitored by the two sensors are fused, which not only ensures the adequacy of the data quantity, but also ensures the accuracy of the magnetic field data. The vector analysis method is used to obtain the size and direction of the magnetic field monitored by the two sensors, thereby improving the accuracy of the experiment.

[0051] The data after combining the two sensors is shown in the table:

[0052]

[0053] Specifically, the data of the two sensors are combined by applying the vector sum method in physics, that is, the simplest vector calculation method, the parallelogram law, is used to calculate the final combined data.

[0054] By analyzing the data in the table, it can be found that after vector analysis, the magnetic field data measured by the giant magnetoresistance sensor and the fluxgate sensor have an error of only 0.003 from the actual magnetic field value, while the magnetic field intensity obtained by only using the giant magnetoresistance sensor or the fluxgate sensor has a large deviation from the actual value. This shows that combining the giant magnetoresistance sensor and the fluxgate sensor can complement their advantages and disadvantages, and the magnetic field intensity obtained after the combination is closer to the actual value, ensuring the accuracy of the experimental data and improving the accuracy and reliability of the measurement.

[0055] In specific applications, the current is set, and the current passes through the magnetic coil to generate a magnetic field. The data monitored by the two sensors are combined to obtain the size and direction of the changed magnetic field. Secondly, the captured magnetic field signal is converted into a digital format after passing through a signal processing unit and sent to a digital signal processor through a high-speed data channel.

[0056] Following the method of introducing electric field lines to describe the electric field, magnetic flux lines are introduced to describe the magnetic field. The number of magnetic flux lines passing through a curved surface in the magnetic field is called the magnetic flux passing through the curved surface. The calculation formula for the magnetic flux is:

[0057]

[0058] in, Where μ0 is the magnetic permeability in vacuum (constant, μ0=4π×10 -7 m / A); I represents the current, in A; x represents the distance to the conductor, in m.

[0059] The digital signal processor applies a formula to calculate the magnetic flux through the coil, and then combines the induced electromotive force and resistance formula to obtain a formula that can accurately calculate the resistivity of the coil:

[0060]

[0061] Where R represents the resistance of the coil, in Ω; S represents the cross-sectional area of ​​the coil, in m 2 ; L represents the length of the coil, unit is m; the unit of resistivity is Ω·m; Represents the rate of change of magnetic flux.

[0062] During the test, each time a different current value is passed, a different magnetic field will be generated around the magnet coil. According to the resistance calculation formula, the resistance of the coil will also change when different currents are passed. After repeated tests, the corresponding relationship between the changing current and the change in coil resistivity can be obtained:

[0063]

[0064] Among them, S represents the cross-sectional area of ​​the coil, E represents the induced electromotive force generated when current flows through the coil, L represents the length of the coil, and I 真 Indicates the current value monitored by the equipment during the experimental operation, I 设定 Indicates the expected current size in the experimental design; multiple factors such as conductor material and magnetic field strength will affect the current flowing through the coil in the magnetic field. In addition, the equipment for monitoring the current size and manual readings will also bring errors to the current value. In the invention, in order to ensure the accuracy of the experimental data, I 设定 and I 真 , I 真 and I 设定 They all have corresponding resistivities, and a corresponding relationship can be found between the resistivity difference Δρ and ΔI between the two, thereby obtaining a corresponding relationship between current and coil resistivity.

[0065] Then, the added current is fine-tuned based on the applied current. When the current flowing into the coil changes, the magnetic field will also change. The changes in the magnetic field and the changes in the coil resistivity are observed to obtain the corresponding change rules.

[0066] I(A) 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 ρ(Ω·m) 0 0.42 0.81 1.24 1.63 2.04 2.46 2.88

[0067] Finally, the calculated coil resistivity is:

[0068]

[0069] In the formula, N represents the number of turns of the coil; B represents the magnetic field strength; S represents the area of ​​the coil; I represents the current flowing into the coil; L represents the length of the coil; ΔS / Δt represents the area that the magnetic induction intensity B passes through during the changing time.

[0070] The real-time display and storage of data are completed through the display control unit and the data processing unit, which respectively provide functions such as historical data comparison and recording of all relevant parameters of resistivity measurement.

[0071] like Figure 2-Figure 3 As shown, the magnetic moment is a physical quantity that describes the magnetism of a current-carrying coil or a microscopic particle, and its definition is m=i*S*e, where i is the current intensity, S is the coil area, and e is a unit vector related to the current direction or the right-hand spiral. In the present invention, the magnetic moments of the first induction coil and the second induction coil are calculated to measure the strength of the magnetic field. The stronger the magnetic field, the greater the value of the magnetic induction intensity B. Specifically, the magnetic moment m1 and the magnetic moment m2 represent the magnetic moments corresponding to the first induction coil and the second induction coil, respectively; wherein the induced electromotive force generated by the coil satisfies a preset relationship with the magnetic moment.

[0072] Phase Difference represents the difference between the induced electromotive force generated by the first magnetic coil on the first induction coil and the induced electromotive force generated on the second induction coil, and the amplitude value A1 is the amplitude value ratio of the induced electromotive force generated by the first magnetic coil on the first induction coil to the induced electromotive force generated on the second induction coil;

[0073] Phase Difference represents the difference between the induced electromotive force generated by the second magnetic coil on the first induction coil and the induced electromotive force generated on the second induction coil; the amplitude value A2 is the amplitude value ratio of the induced electromotive force generated by the second magnetic coil on the first induction coil and the induced electromotive force generated on the second induction coil;

[0074] The plane formed by the magnet coil, the first induction coil and the second induction coil is taken as a reference to the horizontal plane. The angle corresponding to the maximum second resistivity calculated is set as a, and the angle corresponding to the minimum second resistivity is set as b. The corresponding angles for different second resistivities can be obtained, and thus the angle corresponding to the current value at the current moment can be obtained. When different currents are passed through, the magnetic field will change, causing the coil to deflect, such as Figure 4 As shown; according to the ratio of the induced electromotive force and the amplitude value generated by the first induction coil and the second induction coil, the corresponding second resistivity ρ2 is calculated.

[0075] Specifically, the phase difference Amplitude value A1, phase difference The amplitude value A2 is the result of calculating the induced electromotive force generated between the magnetic coil and the induction coil. When the coil rotates in the magnetic field, the calculation formula for the induced electromotive force generated is:

[0076]

[0077] Where B represents the magnetic field strength, L represents the total length of the line, and v represents the speed at which the coil cuts the magnetic flux lines.

[0078] Depend on Combined to get the phase difference Amplitude value A1 and phase difference After the amplitude value A2 (the induced electromotive force generated by the coil has a corresponding angle and induced electromotive force value, namely A. According to the induced electromotive force generated by the first coil and the second coil, the corresponding φ1, A1, φ2, and A2 can be obtained), A3=(A1+A2) / 2, through The resistivity ρ2 is calculated by A1 and A3, where A1 and A2 are the ratio of the induced electromotive force amplitudes,

[0079] The above provides a more comprehensive and reliable measurement solution for resistivity measurement by taking into account that when the current changes, the magnetic field passing through the coil changes, and the magnetic flux lines will change.

[0080] Finally, the final coil resistivity ρ is obtained according to the first coil resistivity ρ1 and the second coil resistivity ρ2, where ρ=(ρ1+ρ2) / 2.

[0081] The above are only preferred embodiments of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims

1. A non-contact measurement system for the resistivity of an ion implanter coil, characterized in that: It includes a control unit, a magnetic field detection unit and an induction coil unit; the control unit is connected to the magnetic field detection unit, the induction coil unit and the coil to be tested respectively; The magnetic field detection unit is used to detect the magnetic field signal generated by the coil to be tested and send it to the control unit; The induction coil unit is used to generate an induced electromotive force corresponding to the coil to be tested, and send it to the control unit; The control unit is used to receive the magnetic field signal of the magnetic field detection unit and the induced electromotive force of the induction coil unit to calculate the coil resistivity.

2. The non-contact measurement system for the coil resistivity of an ion implanter according to claim 1, characterized in that: The magnetic field detection unit includes a giant magnetoresistance sensor and a fluxgate sensor.

3. The non-contact measurement system for the resistivity of the ion implanter coil according to claim 1, characterized in that: The induction coil unit includes a first induction coil and a second induction coil, and the first induction coil and the second induction coil are respectively located at two ends of the coil to be tested.

4. The non-contact measurement system for the coil resistivity of an ion implanter according to claim 1, 2 or 3, characterized in that: The control unit comprises a signal processing unit, a digital signal processor, a display control unit and a data processing unit; the signal processing unit, the digital signal processor, the display control unit and the data processing unit are connected in sequence.

5. A method for measuring the non-contact measurement system of the coil resistivity of an ion implanter based on any one of claims 1 to 4, characterized in that: Includes steps: The magnetic field detection unit detects the magnetic field signal generated by the coil to be tested and sends it to the control unit; The induction coil unit generates an induced electromotive force corresponding to the coil to be tested, and sends it to the control unit; The control unit receives the magnetic field signal of the magnetic field detection unit to calculate the first coil resistivity, calculates the second coil resistivity according to the induced electromotive force of the induction coil unit; and then obtains the final coil resistivity according to the first coil resistivity and the second coil resistivity.

6. The measuring method according to claim 5, characterized in that: The direction and magnitude of the magnetic field are detected respectively by a giant magnetoresistance sensor and a fluxgate sensor, and the two detection results are fused by a vector analysis method to obtain the resistivity of the first coil.

7. The measuring method according to claim 5 or 6, characterized in that: The corresponding relationship between the magnetic field strength and the coil resistivity is obtained as: Where S represents the cross-sectional area of ​​the coil, E represents the induced electromotive force, L represents the length of the coil, Itrue represents the monitored coil current value, and Iset represents the preset current; ρ 真 is the resistivity corresponding to I true, ρ 设定 Set the corresponding resistivity for I; Δρ is ρ 真 and ρ 设定 The difference between .

8. The measuring method according to claim 5 or 6, characterized in that: The process of obtaining the resistivity of the second coil is: Obtaining the induced electromotive force of the first induction coil and the induced electromotive force of the second induction coil; The phase difference is obtained based on the induced electromotive force of the first induction coil and the induced electromotive force of the second induction coil. Amplitude value A1, phase difference Amplitude value A2; where phase difference represents the difference between the induced electromotive force generated by the first magnetic coil on the first induction coil and the induced electromotive force generated on the second induction coil; the amplitude value A1 is the amplitude value ratio of the induced electromotive force generated by the first magnetic coil on the first induction coil and the induced electromotive force generated on the second induction coil; the phase difference represents the difference between the induced electromotive force generated by the second magnetic coil on the first induction coil and the induced electromotive force generated on the second induction coil; the amplitude value A2 is the amplitude value ratio of the induced electromotive force generated by the second magnetic coil on the first induction coil and the induced electromotive force generated on the second induction coil; According to the phase difference Amplitude value A1, phase difference Amplitude value A2 results in the resistivity of the second electrical coil.

9. The measuring method according to claim 8, characterized in that: According to the phase difference Amplitude value A1, phase difference The amplitude value A2 obtains the angle corresponding to the current value at the current moment and amplitude value A3, through The second resistivity ρ2 is calculated by A3.

10. The measuring method according to claim 5 or 6, characterized in that: The final coil resistivity ρ is obtained according to the first coil resistivity ρ1 and the second coil resistivity ρ2, wherein ρ=(ρ1+ρ2) / 2.

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