Method for monitoring ion implantation dose, computer device, storage medium and product

Abstract

The application relates to the technical field of ion implantation processing, and discloses an ion implantation dose monitoring method, computer equipment, a storage medium and a product, the method comprising the following steps: performing ion implantation processing on a semiconductor wafer; determining the first reflectivity of the semiconductor wafer after ion implantation processing; and monitoring the ion implantation dose based on the first reflectivity. The ion implantation dose and stability thereof can be monitored through the reflectivity of the surface of the semiconductor wafer, so that peeling of the wafer surface caused by high-temperature activation after doping of some ions (such as hydrogen ions and helium ions) can be avoided, and the dose and stability of the doped ions cannot be reflected by measuring the square resistance.

Description

Technical Field

[0001] This invention relates to the field of ion implantation technology, and specifically to a method for monitoring ion implantation dosage, a computer device, a storage medium, and a product. Background Technology

[0002] In the manufacturing process of Silicon on Insulator (SOI) wafers using SmartCut technology, hydrogen ion implantation is involved to enable wafer splitting in subsequent processes. If the hydrogen ion implantation dose is unstable during the process, the wafer may fail to split or exhibit abnormal splitting, ultimately leading to the scrapping of the SOI wafer.

[0003] Currently, common N-type implanted ions, such as arsenic (AS+) or phosphorus (P+), can be rapidly thermally implanted using wafer control under specific ion implantation conditions. The stability of the ion implantation dose can then be measured by measuring the sheet resistance. However, when testing hydrogen ion implantation dose and its stability using the above method, the high-temperature environment required for sheet resistance measurement can easily cause hydrogen ions to form hydrogen gas (H2) at the implantation layer interface, leading to wafer surface peeling and even fragmentation. Summary of the Invention

[0004] In view of this, the present invention provides a method, computer device, storage medium and product for monitoring ion implantation dose, to solve the problem that it is difficult to effectively monitor the hydrogen ion implantation process dose and its stability in wafers by measuring the sheet resistance after heat treatment.

[0005] In a first aspect, the present invention provides a method for monitoring ion implantation dose, the method comprising: performing ion implantation on a semiconductor wafer; determining a first reflectivity of the semiconductor wafer after ion implantation; and monitoring the ion implantation dose based on the first reflectivity.

[0006] The ion implantation dose monitoring method provided in this embodiment determines the first reflectivity after ion implantation of the semiconductor wafer, and then monitors the ion implantation dose based on the first reflectivity. This avoids the high-temperature heat treatment environment, thereby effectively monitoring the ion implantation dose and its stability, and reducing the product risks caused by unstable ion implantation dose.

[0007] In one alternative implementation, monitoring the ion implantation dose based on a first reflectivity includes: monitoring whether the ion implantation dose is stable based on the first reflectivity.

[0008] In one optional implementation, monitoring whether the ion implantation dose is stable based on the first reflectivity includes: determining the range of variation of the first reflectivity based on a first correspondence and a first preset reflectivity, wherein the first correspondence is used to characterize the sensitivity of the first reflectivity to the ion implantation dose; if the first reflectivity is within the range of variation of the first reflectivity, the ion implantation dose is stable.

[0009] In this embodiment, the range of first reflectance variation is determined based on the first correspondence and the first preset reflectance, and then the stability of the ion implantation dose is determined based on whether the first reflectance is within the range of first reflectance variation, which can improve the accuracy of the judgment.

[0010] In one alternative implementation, before monitoring whether the ion implantation dose is stable based on the first reflectivity, the method further includes: fitting and determining a first correspondence based on the reflectivity of the semiconductor wafer at multiple different ion implantation doses.

[0011] In one alternative embodiment, before performing ion implantation on the semiconductor wafer, the method further includes: determining a second reflectivity of the semiconductor wafer before ion implantation; and monitoring whether the ion implantation dose is stable based on the first reflectivity, including: determining a relative reflectivity based on the first and second reflectivity; and determining whether the ion implantation dose is stable based on the relative reflectivity.

[0012] In this implementation, ion implantation is performed after the second reflectivity is determined. Then, the relative reflectivity is determined based on the first and second reflectivities. Based on the relative reflectivity, the stability of the ion implantation dose is determined through statistical process control. This reduces interference from external factors such as the test environment and test instruments, and further improves the accuracy of determining the stability of the ion implantation dose.

[0013] In one optional implementation, determining whether the ion implantation dose is stable based on relative reflectivity includes: determining the range of relative reflectivity variation based on a second correspondence and a second preset reflectivity, wherein the second correspondence is used to characterize the sensitivity of relative reflectivity to the ion implantation dose; if the relative reflectivity is within the range of relative reflectivity variation, the ion implantation dose is stable.

[0014] In one alternative implementation, monitoring the ion implantation dose based on a first reflectivity includes: determining whether the ion implantation dose is within a target dose fluctuation range based on the first reflectivity; and stopping the ion implantation process on the semiconductor wafer when the ion implantation dose is within the target dose fluctuation range.

[0015] In one alternative embodiment, the semiconductor wafer is a P-type substrate doped wafer or an N-type substrate doped wafer.

[0016] In one alternative implementation, the ion types used in the ion implantation process include hydrogen ions, helium ions, argon ions, or xenon ions.

[0017] In a second aspect, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to perform the method described in the first aspect or any corresponding embodiment thereof.

[0018] Thirdly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to perform the method described in the first aspect or any corresponding embodiment thereof.

[0019] Fourthly, the present invention provides a computer program product, including computer instructions for causing a computer to perform the method described in the first aspect or any corresponding embodiment thereof. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of the present invention, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a flowchart illustrating a method for monitoring ion implantation dosage according to an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of a two-dimensional map of the absolute reflectance at 49 points measured according to an embodiment of the present invention;

[0023] Figure 3 This is a flowchart illustrating another method for monitoring ion implantation dosage according to an embodiment of the present invention;

[0024] Figure 4 This is a schematic diagram of the path of light on a semiconductor wafer according to an embodiment of the present invention;

[0025] Figure 5 This is a schematic diagram of the first correspondence at a wavelength of 633nm according to an embodiment of the present invention;

[0026] Figure 6 This is a schematic diagram of the first correspondence at a wavelength of 248nm according to an embodiment of the present invention;

[0027] Figure 7This is a schematic diagram of the first correspondence at a wavelength of 193nm according to an embodiment of the present invention;

[0028] Figure 8 This is a flowchart illustrating another method for monitoring ion implantation dosage according to an embodiment of the present invention;

[0029] Figure 9 This is a structural block diagram of an ion implantation dose monitoring device according to an embodiment of the present invention;

[0030] Figure 10 This is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Silicon on Insulator (SOI) incorporates a buried oxide (BOX) layer between the top silicon layer and the substrate. This structure electrically isolates the top silicon layer and the substrate, reducing parasitic capacitance between transistors, decreasing signal transmission delay, and increasing circuit operating speed. It also reduces leakage current from the substrate to the top silicon device, thereby lowering circuit power consumption.

[0033] Currently, SOI wafers can be manufactured based on Smart Cut technology. Specifically, firstly, two silicon (Si) wafers are oxidized at high temperature to form surface oxide layers. Then, a large number of hydrogen ions (H+) are implanted into the oxide layer of one of the wafers using an ion implanter to form a hydrogen ion implantation layer on the silicon substrate. Subsequently, the two oxide layers are bonded together by hydrophilic bonding and heated to 400°C to 600°C to cause the hydrogen ion implantation layer to break, separating the excess Si layer. Finally, after annealing and chemical mechanical polishing (CMP), an SOI structure is formed.

[0034] When manufacturing SOI wafers using Smart Cut technology, it is necessary to monitor the stability and uniformity of the ion implantation dose to address issues such as wafer cleaving failure or abnormal cleaving caused by unstable ion implantation doses. Typically, the stability and uniformity of the ion implantation dose are measured by performing high-temperature rapid thermal annealing after ion implantation and then measuring the sheet resistance. However, sheet resistance testing requires a high-temperature annealing process to activate the implanted ions, and hydrogen ions, due to their inherent properties, easily form H2 at high temperatures, leading to wafer peeling or fragmentation. In other words, using sheet resistance to monitor the hydrogen ion implantation dose and its stability can easily damage the silicon wafer, reducing the production yield of SOI wafers.

[0035] In view of this, the present invention provides a method for monitoring ion implantation dose, which determines the ion implantation dose and its stability by using the reflectivity of the semiconductor wafer surface. This method avoids high-temperature heat treatment environments and effectively monitors the ion implantation dose and its stability that may damage or crack the wafer under high-temperature heat treatment environments.

[0036] The ion implantation dose monitoring method provided by this invention can be used in semiconductor manufacturing processes such as ion implantation and rapid thermal processing.

[0037] Figure 1 This is a flowchart illustrating a method for monitoring ion implantation dosage according to an embodiment of the present invention, as shown below. Figure 1 As shown, the method includes the following steps:

[0038] Step S101: Perform ion implantation on the semiconductor wafer.

[0039] Specifically, semiconductor wafers can be ion implanted using an ion implanter. The process parameters for ion implantation (such as ion type and ion implantation energy) can be determined by the designer based on process requirements.

[0040] This invention does not specifically limit the type of ion. For example, the ion type can be hydrogen ion, helium ion, argon ion or xenon ion, which are ions that easily generate gas molecules at high temperatures. The ion type can also be conventionally injected ions such as arsenic ion or phosphorus ion.

[0041] For example, the semiconductor wafer can be a P-type substrate doped wafer or an N-type substrate doped wafer.

[0042] Step S102: Determine the first reflectivity of the semiconductor wafer after ion implantation.

[0043] Specifically, the first reflectivity refers to the absolute reflectivity of the semiconductor wafer after ion implantation.

[0044] After ion implantation of a semiconductor wafer, the absolute reflectivity of a target location (such as the center of the semiconductor wafer) can be directly determined as the first reflectivity, or the absolute reflectivity of multiple preset locations can be determined as the first reflectivity. These preset locations can be set by the designer based on experience.

[0045] For example, such as Figure 2 As shown, the absolute reflectance at 49 locations on the semiconductor wafer surface can be determined, and the average of these 49 locations is then used as the first reflectance. Furthermore, the two-dimensional map presented by the measured absolute reflectance at these 49 points can reflect the uniformity of the ion implantation dose to a certain extent. Specifically, the uniformity can be characterized based on the standard deviation of the measured absolute reflectance at these 49 points.

[0046] For example, an ion implantation dose monitoring device can use an optical measuring instrument to determine the absolute reflectivity by detecting the spectral characteristics of light after reflection on the surface of a semiconductor wafer; the ion implantation dose monitoring device can also emit polarized light onto the semiconductor wafer and determine the absolute reflectivity by measuring the change in the polarization state (such as amplitude and phase) of the reflected light; the ion implantation dose monitoring device can also emit light onto the surface of the semiconductor wafer from multiple angles and determine the absolute reflectivity by measuring the intensity of the reflected light at different angles.

[0047] Step S103: Monitor the ion implantation dose based on the first reflectivity.

[0048] Specifically, after determining the first reflectivity, it can be used to determine whether the ion implantation dose is stable, or whether the ion implantation dose has reached the target dose. The target dose can be configured by the designer according to process requirements.

[0049] For example, after determining the first reflectivity, the stability of the ion implantation dose can be monitored using statistical process control (SPC).

[0050] SPC (Statistical Process Control) is a statistical method used to monitor the production process. By statistically analyzing the data, it can be determined whether the production process is stable and under control. In this invention, the data refers to the reflectivity of the semiconductor wafer, and the production process refers to the ion implantation process.

[0051] Specifically, after determining the first reflectivity, if the first reflectivity is within the statistical control range, the ion implantation dose is stable; if the first reflectivity is outside the statistical control range, the ion implantation dose is unstable, and technical personnel can be notified to handle the situation (such as inspection or maintenance) through devices such as alarms.

[0052] The statistical control range can be determined based on historical data or pre-set standards. For example, the statistical control range can be [(X-3σ), (X+3σ)]. X represents the average reflectance, and σ represents the standard deviation. The average reflectance refers to the average absolute reflectance of semiconductor wafers after ion implantation treatment obtained from the previous N months. The standard deviation refers to the standard deviation of the absolute reflectance of semiconductor wafers after ion implantation treatment obtained from the previous N months. N is greater than 0. For example, N can be 1, 1.5, 3, or 5, etc.

[0053] That is, when the first reflectivity is less than or greater than At that time, the ion implantation dose is unstable, and the first reflectivity is greater than or equal to and the first reflectivity is less than or equal to At that time, ion implantation was stable.

[0054] Specifically, ion implantation dose stability can be determined online or offline using SPC (Static Computational Processing). Online determination involves continuously measuring the primary reflectivity of the semiconductor wafer during production and using this primary reflectivity to determine ion implantation stability. Offline determination involves sampling semiconductor wafers after they are removed from the production line, detecting the primary reflectivity of the sampled wafers, and then using this primary reflectivity to determine ion implantation stability.

[0055] Online testing can quickly identify potential problems and adjust production parameters in a timely manner, while offline testing can reduce the number of tests and improve production efficiency.

[0056] The ion implantation dose monitoring method provided in this embodiment determines the first reflectivity after ion implantation of the semiconductor wafer, and then monitors the ion implantation dose based on the first reflectivity. This avoids the high-temperature heat treatment environment, thereby effectively monitoring the ion implantation dose and reducing the product risk caused by unstable ion implantation dose.

[0057] Figure 3 This is a flowchart illustrating another method for monitoring ion implantation dosage according to an embodiment of the present invention, as shown below. Figure 3 As shown, the method includes the following steps:

[0058] Step S301: Perform ion implantation on the semiconductor wafer.

[0059] Please see details Figure 1 Step S101 of the illustrated embodiment will not be described again here.

[0060] Step S302: Determine the first reflectivity of the semiconductor wafer after ion implantation.

[0061] In this embodiment, an optical measuring instrument is used to determine the first reflectance based on spectral reflectance (SR).

[0062] Specifically, such as Figure 4 As shown, when a beam of light (i.e., incident light 421) irradiates the surface of the semiconductor wafer 410, part of the light is transmitted (i.e., transmitted light 422), and the other part of the light is reflected (i.e., reflected light 423). The optical measuring instrument decomposes the reflected light into light of different wavelengths through a beam splitting device (such as a grating), and then measures the intensity of the reflected light at each wavelength. The ratio of these reflected light intensities to the incident light intensities at different wavelengths constitutes the spectral reflectance curve. Based on the spectral reflectance curve, the first reflectance can be determined.

[0063] Step S303: Based on the reflectivity of the semiconductor wafer under multiple different ion implantation doses, a first correspondence is determined by fitting.

[0064] The first correspondence is used to characterize the sensitivity of the first reflectivity to the ion implantation dose.

[0065] Specifically, after obtaining the maximum and minimum ion implantation doses, the ion implantation doses are grouped according to a certain gradient to obtain multiple different ion implantation doses. Then, the semiconductor wafer is sequentially ion implanted in ascending order of ion implantation doses to determine the reflectivity corresponding to each different ion implantation dose. The maximum and minimum ion implantation doses and the gradient can be determined by the designer, and the ion implantation energy is the same; for example, the ion implantation energy can be greater than 1000 eV.

[0066] After determining the reflectivity of a semiconductor wafer at multiple different ion implantation doses, a first correspondence can be determined using fitting software (such as Excel). The first correspondence can be as follows: Figures 5 to 7 As shown, where, Figure 5 This indicates the first correspondence at a wavelength of 633nm. Figure 6 This represents the first correspondence at a wavelength of 248nm. Figure 7 This indicates the first correspondence at a wavelength of 193nm.

[0067] The first correspondence at a wavelength of 633nm can be y = (7E-20)x + 0.3471. At this point, the correlation coefficient R0 2 =0.994; the first correspondence at a wavelength of 248nm can be y = (2E-19)x + 0.6734, at which point the correlation coefficient R is 0.994. 2=0.9989; the first correspondence at a wavelength of 193nm can be y = (9E-20)x + 0.6713, at which point the correlation coefficient R 2 =0.9908.

[0068] Specifically, at a wavelength of 248 nm, the reflectance corresponding to different ion implantation doses can be shown in Table 1, where the absolute reflectance for each 1% change in ion implantation dose is 0.00012.

[0069] Table 1

[0070]

[0071] Step S304: Based on the first reflectivity, determine whether the ion implantation dose is stable.

[0072] Specifically, step S304 includes:

[0073] Step S3041: Based on the first correspondence and the first preset reflectivity, determine the range of variation of the first reflectivity.

[0074] The first preset reflectivity can be configured by the designer based on historical data. For example, the first preset reflectivity can be the average absolute reflectivity of the ion semiconductor wafers detected in the previous N months after ion implantation treatment, where N is greater than 0. The range of first reflectivity variation represents the range (interval) of first reflectivity variation caused by the dose deviation allowed by the designer.

[0075] Specifically, (first preset reflectivity ± 3ΔR1) can be defined as the first reflectivity variation range, where ΔR1 represents the first reflectivity change value corresponding to a 1% change in ion implantation dose, and ΔR1 can be determined through the first correspondence.

[0076] In step S3042, if the first reflectivity is within the range of the first reflectivity variation, the ion implantation dose is stable.

[0077] Specifically, when the first reflectivity is greater than the maximum value of the first reflectivity variation range or less than the minimum value of the first reflectivity variation range, the ion implantation dose is unstable; when the first reflectivity is greater than or equal to the minimum value of the first reflectivity variation range and less than or equal to the maximum value of the first reflectivity variation range, the ion implantation dose is stable.

[0078] For example, if the first reflectivity is greater than (first preset reflectivity + 3ΔR1) or less than (first preset reflectivity - 3ΔR1), then ion implantation is unstable; if the first reflectivity is greater than or equal to (first preset reflectivity - 3ΔR1) and less than or equal to (first preset reflectivity + 3ΔR1), then ion implantation is stable.

[0079] Step S305: Based on the first reflectivity, determine whether the ion implantation dose is within the target dose fluctuation range.

[0080] The target dose fluctuation range can be configured by the designer based on process requirements.

[0081] Specifically, when the first reflectivity is within the target reflectivity variation range, the ion implantation dose is within the target dose fluctuation range; when the first reflectivity is not within the target reflectivity variation range, the ion implantation dose is not within the target dose fluctuation range. The maximum value of the target reflectivity variation range is the absolute reflectivity of the semiconductor wafer surface when the ion implantation dose is at the maximum value of the target dose fluctuation range, and the minimum value of the target reflectivity variation range is the absolute reflectivity of the semiconductor wafer surface when the ion implantation dose is at the minimum value of the target dose fluctuation range. The target reflectivity variation range can be determined based on the first correspondence and the target dose fluctuation range, or it can be determined experimentally.

[0082] Step S306: When the ion implantation dose is within the target dose fluctuation range, stop the ion implantation process on the semiconductor wafer.

[0083] Specifically, during the ion implantation process on the semiconductor wafer, a first reflectivity is determined at preset intervals. Then, based on the first reflectivity, it is determined whether the ion implantation dose is stable and whether it is within the target dose fluctuation range. If the ion implantation dose is stable and not within the target dose fluctuation range, the ion implantation process on the semiconductor wafer continues. If the ion implantation dose is unstable or within the target dose fluctuation range, the ion implantation process on the semiconductor wafer is stopped.

[0084] For example, the step of monitoring the ion implantation dose based on the first reflectivity may include steps S304 to S306, or may include only step S304, or may include only steps S305 and S306.

[0085] In this embodiment, after ion implantation of the semiconductor wafer, the first reflectivity is determined using an optical measuring instrument based on SR (reflectance). This measurement can be performed without contact, avoiding the introduction of contaminants or damage to the semiconductor wafer surface. Furthermore, SR measurement can detect minute changes on the wafer surface, improving the accuracy of the determined first reflectivity. After determining the first correspondence, the range of first reflectivity variation is determined based on the first correspondence and a first preset reflectivity. Then, whether the ion implantation dose is stable is determined based on whether the first reflectivity is within the range of first reflectivity variation, improving the accuracy of the judgment. After determining the first reflectivity, whether the ion implantation dose is within the target dose fluctuation range is determined based on the first reflectivity. Once it is determined that the ion implantation dose is within the target dose fluctuation range, ion implantation of the semiconductor wafer is stopped. This allows for real-time monitoring of the ion implantation dose, preventing excessive ion concentration in the semiconductor wafer.

[0086] Figure 8 This is a flowchart illustrating another method for monitoring ion implantation dosage according to an embodiment of the present invention, as shown below. Figure 8 As shown, the method includes the following steps:

[0087] Step S801: Determine the second reflectivity of the semiconductor wafer before ion implantation.

[0088] The second reflectivity refers to the absolute reflectivity of the semiconductor wafer before ion implantation. Before ion implantation, the absolute reflectivity of the target location (such as the center of the semiconductor wafer) can be directly determined as the second reflectivity, or the absolute reflectivity of multiple preset locations can be determined as the second reflectivity.

[0089] Specifically, the second reflectivity can be determined in the same way as the first reflectivity. For example, the second reflectivity can be measured based on SR using an optical measuring instrument.

[0090] Step S802: Perform ion implantation on the semiconductor wafer.

[0091] Please see details Figure 1 Step S101 of the illustrated embodiment will not be described again here.

[0092] Step S803: Determine the first reflectivity of the semiconductor wafer after ion implantation.

[0093] Please see details Figure 1 Step S102 of the illustrated embodiment or Figure 3 Step S302 of the illustrated embodiment will not be described again here.

[0094] Step S804: Based on the first reflectivity, determine whether the ion implantation dose is stable.

[0095] Specifically, step S804 may include steps S8041 and S8042:

[0096] Step S8041: Determine the relative reflectance based on the first reflectance and the second reflectance.

[0097] Specifically, the ratio of the second reflectivity to the first reflectivity can be defined as the relative reflectivity, i.e., R3 = R2 / R1, where R3 represents the relative reflectivity, R2 represents the second reflectivity, and R1 represents the first reflectivity.

[0098] For example, the absolute value of the difference between the second reflectivity and the first reflectivity can also be determined as the relative emissivity, i.e., R3 = |R1 - R2|.

[0099] Step S8042: Determine whether the ion implantation dose is stable based on the relative reflectivity.

[0100] Specifically, step S8042 above may include steps a1 and a2:

[0101] Step a1: Determine the range of relative reflectance variation based on the second correspondence and the second preset reflectance.

[0102] The second correspondence is used to characterize the sensitivity of relative reflectivity to ion implantation dose. The second preset reflectivity can also be configured by the designer based on historical data. For example, the second preset reflectivity can be the average of the relative reflectivity of ion semiconductor wafers obtained in the previous N months before and after ion implantation treatment, where N is greater than 0. The range of relative reflectivity variation represents the range (interval) of relative reflectivity variation caused by the dose deviation allowed by the designer.

[0103] Specifically, (second preset reflectance ± 3ΔR2) can be defined as the range of relative reflectance variation, where ΔR2 represents the relative reflectance change value corresponding to a 1% change in ion implantation dose, and ΔR2 can be determined through the second correspondence.

[0104] For example, after determining the second reflectivity, an ion implantation process is performed on the semiconductor wafer to determine the first reflectivity corresponding to multiple different ion implantation doses. Then, based on the second reflectivity and the first reflectivity corresponding to the multiple different ion implantation doses, the relative reflectivity corresponding to different ion implantation doses can be determined. Subsequently, a second correspondence can be determined by fitting software.

[0105] Step a2: If the relative reflectivity is within the range of relative reflectivity variation, then the ion implantation dose is stable.

[0106] Specifically, when the relative reflectivity is greater than the maximum value of the relative reflectivity variation range or less than the minimum value of the relative reflectivity variation range, the ion implantation dose is unstable; when the relative reflectivity is greater than or equal to the minimum value of the relative reflectivity variation range, and when the relative reflectivity is less than or equal to the maximum value of the relative reflectivity variation range, the ion implantation dose is stable.

[0107] For example, if the relative reflectance is greater than (second preset reflectance + 3ΔR2) or less than (second preset reflectance - 3ΔR2), then ion implantation is unstable; if the relative reflectance is greater than or equal to (second preset reflectance - 3ΔR2) and less than or equal to (second preset reflectance + 3ΔR2), then ion implantation is stable.

[0108] In this implementation, ion implantation is performed after the second reflectivity is determined. Then, the relative reflectivity is determined based on the first and second reflectivities, and the stability of the ion implantation dose is determined based on the relative reflectivity. This reduces interference from external factors such as the test environment and test instruments, and further improves the accuracy of determining whether the ion implantation dose is stable.

[0109] This embodiment also provides an ion implantation dose monitoring device for implementing the above embodiments and preferred embodiments; details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0110] This embodiment provides a device for monitoring ion implantation dosage, such as... Figure 9 As shown, it includes:

[0111] Ion implantation processing module 901 is used for ion implantation processing of semiconductor wafers;

[0112] The first determining module 902 is used to determine the first reflectivity of the semiconductor wafer after ion implantation.

[0113] Monitoring module 903 is used to monitor the ion implantation dose based on the first reflectivity.

[0114] In some alternative implementations, the monitoring module 903 includes:

[0115] The first monitoring unit is used to monitor whether the ion implantation dose is stable based on the first reflectivity.

[0116] In some alternative implementations, the first monitoring unit includes:

[0117] The first determining unit is used to determine the range of variation of the first reflectance based on the first correspondence and the first preset reflectance, wherein the first correspondence is used to characterize the sensitivity of the first reflectance to the ion implantation dose;

[0118] The second determining unit is used to ensure that the ion implantation dose is stable if the first reflectivity is within the range of the first reflectivity variation.

[0119] In some alternative embodiments, the apparatus further includes:

[0120] The second determining module is used to fit and determine the first correspondence based on the reflectivity of the semiconductor wafer under multiple different ion implantation doses.

[0121] In some alternative embodiments, the apparatus further includes:

[0122] The third determining module is used to determine the second reflectivity of the semiconductor wafer before ion implantation.

[0123] The first monitoring unit also includes:

[0124] The third determining unit is used to determine the relative reflectance based on the first reflectance and the second reflectance;

[0125] The fourth determining unit is used to determine whether the ion implantation dose is stable based on the relative reflectivity.

[0126] In some alternative implementations, the fourth determining unit includes:

[0127] The first determining subunit is used to determine the range of relative reflectance variation based on the second correspondence and the second preset reflectance, wherein the second correspondence is used to characterize the sensitivity of relative reflectance to ion implantation dose;

[0128] The second determining subunit is used to ensure that the ion implantation dose is stable if the relative reflectivity is within the range of relative reflectivity variation.

[0129] In some alternative implementations, the monitoring module 903 includes:

[0130] The fifth determining unit is used to determine whether the ion implantation dose is within the target dose fluctuation range based on the first reflectivity;

[0131] The stop unit is used to stop ion implantation on a semiconductor wafer when the ion implantation dose is within the target dose fluctuation range.

[0132] In some alternative implementations, the semiconductor wafer is a P-type substrate doped wafer or an N-type substrate doped wafer.

[0133] In some alternative embodiments, the ion type for ion implantation treatment includes at least one of hydrogen ions, helium ions, argon ions, and xenon ions.

[0134] Further functional descriptions of the above modules and units are the same as those in the corresponding embodiments described above, and will not be repeated here.

[0135] In this embodiment, the ion implantation dose monitoring device is presented in the form of a functional unit. Here, a unit refers to an application-specific integrated circuit (ASIC) circuit, a processor and memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.

[0136] In some alternative implementations, the ion implantation dose monitoring device also includes an ion implanter and an optical measuring instrument.

[0137] This invention also provides a computer device, such as... Figure 10 As shown, the computer device includes one or more processors 1010, memory 1020, and interfaces for connecting the components, including high-speed interfaces and low-speed interfaces. The components communicate with each other via different buses and can be mounted on a common motherboard or otherwise installed as needed. The processors can process instructions executed within the computer device, including instructions stored in or on memory to display graphical information of a GUI on external input / output devices (such as display devices coupled to the interfaces). In some alternative implementations, multiple processors and / or multiple buses can be used with multiple memories and multiple memory modules, if desired. Similarly, multiple computer devices can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system). Figure 10 Take the 1010 processor as an example.

[0138] The processor 1010 may be a central processing unit, a network processor, or a combination thereof. The processor 1010 may further include a hardware chip. This hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device may be a complex programmable logic device (CAMP), a field-programmable gate array (FPGA), a general-purpose array logic (GPRS), or any combination thereof.

[0139] The memory 1020 stores instructions executable by at least one processor 1010 to cause at least one processor 1010 to perform the method shown in the above embodiments.

[0140] The memory 1020 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the computer device. Furthermore, the memory 1020 may include high-speed random access memory and may also include non-transient memory, such as at least one disk storage device, flash memory device, or other non-transient solid-state storage device. In some alternative embodiments, the memory 1020 may optionally include memory remotely located relative to the processor 1010, and these remote memories can be connected to the computer device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0141] The memory 1020 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory 1020 may also include a combination of the above types of memory.

[0142] The computer device also includes a communication interface 1030 for communicating with other devices or communication networks.

[0143] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the methods shown in the above embodiments.

[0144] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0145] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0146] In the description of this specification, the references to terms such as "this embodiment," "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0147] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0148] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the present invention.

Claims

1. A method for monitoring ion implantation dosage, characterized in that, The method includes: Ion implantation is performed on a semiconductor wafer, wherein the semiconductor wafer is a wafer that needs to be cleaved during the fabrication of a silicon-on-insulator structure; Determine the first reflectivity of the semiconductor wafer after ion implantation; Based on the first reflectivity, monitor the ion implantation dose; the monitoring of the ion implantation dose based on the first reflectivity includes: monitoring whether the ion implantation dose is stable based on the first reflectivity. The step of monitoring whether the ion implantation dose is stable based on the first reflectivity includes: Based on the first correspondence relationship, the first reflectance change value corresponding to the 1% ion implantation dose change and the first preset reflectance are determined, and the range of first reflectance change is determined. The first correspondence relationship is used to characterize the sensitivity of the first reflectance to the ion implantation dose. The first preset reflectance is the average absolute reflectance of the ion semiconductor wafer after ion implantation treatment obtained in the previous N months, where N is greater than 0. If the first reflectivity is within the range of the first reflectivity variation, the ion implantation dose is stable; The method of monitoring the ion implantation dose based on the first reflectivity further includes: Based on the first reflectivity, determine whether the ion implantation dose is within the target dose fluctuation range; When the ion implantation dose is stable and not within the target dose fluctuation range, the semiconductor wafer continues to undergo ion implantation. When the ion implantation dose is unstable or within the target dose fluctuation range, the ion implantation process on the semiconductor wafer shall be stopped.

2. The method according to claim 1, characterized in that, Before monitoring whether the ion implantation dose is stable based on the first reflectivity, the method further includes: The first correspondence is determined by fitting the reflectivity of the semiconductor wafer under multiple different ion implantation doses.

3. The method according to claim 1, characterized in that, Prior to ion implantation of the semiconductor wafer, the method further includes: Determine the second reflectivity of the semiconductor wafer prior to ion implantation; The step of monitoring whether the ion implantation dose is stable based on the first reflectivity includes: The relative reflectance is determined based on the first reflectance and the second reflectance; Based on the relative reflectivity, determine whether the ion implantation dose is stable; Determining whether the ion implantation dose is stable based on the relative reflectivity includes: Based on the relative reflectance change value corresponding to a 1% change in ion implantation dose determined by the second correspondence and the second preset reflectance, the range of relative reflectance change is determined. The second correspondence is used to characterize the sensitivity of the relative reflectance to the ion implantation dose, and the second preset reflectance is the average value of the relative reflectance of the ion semiconductor wafer before and after ion implantation treatment obtained from the previous N months. If the relative reflectance is within the range of relative reflectance variation, the ion implantation dose is stable.

4. The method according to any one of claims 1 to 3, characterized in that, The semiconductor wafer is a P-type substrate doped wafer or an N-type substrate doped wafer.

5. The method according to any one of claims 1 to 3, characterized in that, The types of ions used in ion implantation treatment include hydrogen ions, helium ions, argon ions, or xenon ions.

6. A computer device, characterized in that, include: A memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, the processor executing the computer instructions to perform the method of any one of claims 1 to 5.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing a computer to perform the method of any one of claims 1 to 5.

8. A computer program product, characterized in that, Includes computer instructions for causing a computer to perform the method of any one of claims 1 to 5.

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