Process analysis method, medium and system for uniformity abnormity of ion implanter
By comparing and analyzing thermal wave and resistance distribution maps on the wafer, the problem of ion implantation uniformity can be accurately diagnosed, the cause of anomalies can be quickly located, costs and time can be reduced, and the process control capability of semiconductor manufacturing can be improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-29
- Publication Date
- 2026-03-13
AI Technical Summary
In existing semiconductor integrated circuit manufacturing technologies, it is difficult to accurately determine the uniformity of ion implantation processes, resulting in high material costs, long production cycles, and an inability to clearly identify the causes of anomalies.
By performing thermal wave testing and four-probe testing on the same wafer, thermal wave distribution maps and resistance distribution maps are generated. Abnormal areas are identified through comparative analysis, and abnormal ion implantation dose and angle are distinguished.
It enables rapid and precise location of the root cause of ion implantation uniformity problems, saves wafer material and process debugging time, and improves the control capabilities and product yield of semiconductor manufacturing.
Smart Images
Figure CN121666038A_ABST
Abstract
Description
Technical Field
[0001] This invention mainly relates to the field of ion implantation technology, specifically to a process analysis method, medium, and system for abnormal uniformity in ion implanters. Background Technology
[0002] In semiconductor integrated circuit manufacturing, the verification stage of ion implantation processes often faces the problem of poor uniformity within the wafer, directly affecting the electrical testing performance and product yield of the chip. Currently, when analyzing such problems, the industry mostly relies on the process of elimination to trace the source, failing to fundamentally distinguish the impact of ion implantation dosage and angle on the process results, leading to high material costs and long development cycles for solutions.
[0003] In chip manufacturing, the ion implantation process lacks online testing data support, relying solely on offline data for subsequent analysis. This presents a challenge for process engineers to quickly locate problems. Furthermore, under the dual pressures of efficiency and cost, accurately determining the causes of anomalies in the ion implantation process becomes crucial for improving process control capabilities.
[0004] Current conventional methods primarily exert some control over the beam by adjusting its shape. However, more than twenty parameters affect the beam, and repeated adjustments often fail to pinpoint the root cause of the problem. This not only significantly increases the number of wafers used but also prolongs the solution cycle and raises costs. Furthermore, it remains unclear whether the anomaly originates from the ion implantation angle or the implantation dose. Therefore, existing methods have limitations in both efficiency and accuracy, and cannot fundamentally solve the uniformity problem. Summary of the Invention
[0005] To address the technical problems existing in the prior art, this invention provides a process analysis method, medium, and system for ion implanter uniformity anomalies that enables rapid root cause diagnosis of ion implantation uniformity problems.
[0006] To solve the above-mentioned technical problems, the technical solution proposed by this invention is as follows: A process analysis method for abnormal uniformity in an ion implanter includes the following steps: S1. Obtain and analyze the ionic parameters of the problematic wafer to determine if there are any process parameters that cause non-uniformity; if not, proceed to step S2. S2. Using the same ion implantation parameters as the problematic wafer, re-implant a new wafer and perform thermal wave testing on this wafer to obtain thermal wave values and coordinates at multiple measurement points, generating a thermal wave distribution map; S3. Anneal the wafer that has completed the thermal wave test in step S2 to repair the lattice damage caused by ion implantation. Then, perform a resistance test on the repaired wafer to obtain the resistance values and coordinates of multiple measurement points and generate a resistance distribution map. S4. Compare and analyze the thermal wave distribution map and the resistance distribution map. By identifying the changing trends of abnormal areas in the two distribution maps, the root cause of the uniformity problem can be determined: if the thermal wave value and the resistance value change in opposite directions in the abnormal area, it is determined that the ion implantation dose is abnormal; if the thermal wave value and the resistance value change in the same direction in the abnormal area, it is determined that the ion implantation angle is abnormal.
[0007] Preferably, the coordinates of the corresponding measurement points in the thermal wave distribution map generated in step S2 and the resistance distribution map generated in step S3 are consistent.
[0008] Preferably, in step S4, the unidirectional change specifically means that the heat wave value and the resistance value are both high, or the heat wave value and the resistance value are both low.
[0009] Preferably, in step S4, the reverse change specifically means: the heat wave value is high while the resistance value is low, or the heat wave value is low while the resistance value is high.
[0010] Preferably, in step S2, the thermal wave value at the measurement point on the wafer surface is measured using a thermal wave probe during ion implantation.
[0011] Preferably, in step S3, a four-probe tester is used to measure the resistance at measurement points on the wafer surface.
[0012] Preferably, after step S4, a root cause report is output based on the comparison results to guide process adjustments.
[0013] The present invention also discloses a computer program product, comprising a computer program that, when executed by a processor, performs the steps of the method described above.
[0014] The present invention further discloses a computer-readable storage medium having a computer program stored thereon, the computer program executing the steps of the method described above when run by a processor.
[0015] The present invention also discloses a process analysis system for abnormal uniformity of ion implanter, comprising a memory and a processor connected to each other, wherein the memory stores a computer program, and the computer program executes the steps of the method described above when run by the processor.
[0016] Compared with the prior art, the advantages of the present invention are as follows: This invention achieves rapid root cause diagnosis of ion implantation uniformity problems by sequentially performing and correlating thermal wave testing and four-probe testing on the same wafer. Utilizing the physical correlation and response differences between the two tests in terms of lattice damage and electrical resistance, this method can clearly distinguish between dose anomalies and angle anomalies during ion implantation. It fundamentally solves the problems of high trial-and-error costs and long cycles caused by traditional methods relying on elimination and blindly adjusting beam parameters. Ultimately, it achieves the significant effect of accurately locating the root cause of problems using only one wafer, thereby greatly saving wafer material and process debugging time and effectively improving the control capability and product yield of semiconductor manufacturing processes. Attached Figure Description
[0017] Figure 1 The flowchart in an embodiment is a process analysis method for abnormal uniformity of the ion implanter according to the present invention.
[0018] Figure 2 This is a schematic diagram of the TW map and RS map of the present invention; where (a) is the TW map and (b) is the RS map. Detailed Implementation
[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0020] like Figure 1 As shown, the process analysis method for abnormal uniformity of ion implantation provided in this embodiment of the invention includes the following steps: S1. Analyze the injection parameters of the problem piece. The process begins by organizing the problem data corresponding to the problematic wafer to analyze whether there are any obvious abnormalities in the implantation parameters, such as whether the implantation angle and implantation dose are completed normally, and whether there are any alarm prompts during the implantation process; if there are alarms, it may cause problems with ion implantation uniformity; if not, proceed to S2. S2. Using the same ion implantation parameters as the problematic wafer, re-implant a wafer and use thermal wave testing equipment (such as a thermal wave probe) to measure the degree of lattice damage (thermal wave value, TW value) on the wafer surface during ion implantation. The measurement points should be greater than 52, covering the entire area of the wafer. Export the coordinate system of the measurement points and the corresponding thermal wave value (TW value) together for analysis to generate a thermal wave distribution map (TW map). S3. Anneal the wafers that have completed thermal wave testing to repair the lattice damage on the wafer surface caused by ion implantation; Use a four-probe tester to measure the surface resistance of the wafer, with more than 49 measurement points to ensure that they correspond to the positions of the thermal wave test points. Export the coordinates of the measurement points and their corresponding resistance values (RS values), and generate a resistance distribution map (RS map); S4. Overlay or compare the thermal wave distribution map (TW map) with the electrical resistance distribution map (RS map) to identify abnormal areas; Specifically, the TW map and RS map are compared and analyzed. The TW value anomalies and RS value anomalies are compared. If the TW value is high (low) and the RS value is low (high) at the anomaly point, that is, the TW value and RS value are opposite, then the uniformity anomaly point is caused by the dosage problem. Among them, a high TW value indicates large lattice damage, and a low resistance value indicates good conductivity. If the TW value is low (high) and the RS value is low (high) at the abnormal location, that is, the TW value and RS value are both high or both low, then the uniformity anomaly point is caused by an angle problem.
[0021] From a dosage perspective: a high RS value indicates a low injection dose, while a low RS value indicates a high injection dose; a high TW value indicates a high injection dose, while a low TW value indicates a low injection dose. From the perspective of injection: a high RS value indicates a high injection angle; a high TW value also indicates a high injection angle.
[0022] For example, Figure 2 In the TW map of (a), the TW values are lower on the left and higher on the right. Figure 2 In the RS map in (b), the RS values at the same location show a left-high and right-low pattern, that is, the TW value and RS value change in opposite directions, which indicates that the anomaly in uniformity is caused by a dose problem.
[0023] Step S5. Based on the comparison results, output a root cause report to guide process adjustments and end this analysis process.
[0024] This invention achieves rapid root cause diagnosis of ion implantation uniformity problems by sequentially performing and correlating thermal wave testing and four-probe testing on the same wafer. Utilizing the physical correlation and response differences between the two tests in terms of lattice damage and resistivity, this method can clearly distinguish between dose anomalies and angle anomalies during ion implantation. It fundamentally solves the problems of high trial-and-error costs and long cycles caused by traditional methods relying on elimination and blindly adjusting beam parameters. Ultimately, it achieves the significant effect of accurately locating the root cause of problems using only one wafer, thereby greatly saving wafer material and process debugging time and effectively improving the control capability and product yield of semiconductor manufacturing processes.
[0025] The present invention also discloses a computer program product, comprising a computer program that, when executed by a processor, performs the steps of the method described above.
[0026] The present invention further discloses a computer-readable storage medium having a computer program stored thereon, the computer program executing the steps of the method described above when run by a processor.
[0027] The present invention also discloses a process analysis system for abnormal uniformity of ion implanter, comprising a memory and a processor connected to each other, wherein the memory stores a computer program, and the computer program executes the steps of the method described above when run by the processor.
[0028] The products, media, and systems of the present invention, corresponding to the methods described above, also possess the advantages described above.
[0029] The present invention can implement all or part of the processes in the methods of the above embodiments, or it can be implemented by hardware related to computer program instructions. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, it can implement the steps of the above method embodiments. The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable storage medium includes: any entity or device capable of carrying computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. The memory is used to store computer programs and / or modules. The processor implements various functions by running or executing the computer programs and / or modules stored in the memory, and by calling data stored in the memory. The memory may include high-speed random access memory, as well as non-volatile memory, such as hard disks, RAM, plug-in hard disks, smart media cards (SMC), secure digital (SD) cards, flash cards, at least one disk storage device, flash memory device, or other volatile solid-state storage devices.
[0030] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should be considered within the scope of protection of the present invention.
Claims
1. A process analysis method for abnormal uniformity in an ion implanter, characterized in that, Includes the following steps: S1. Obtain and analyze the ionic parameters of the problematic wafer to determine if there are any process parameters that cause non-uniformity; if not, proceed to step S2. S2. Using the same ion implantation parameters as the problematic wafer, re-implant a new wafer and perform thermal wave testing on this wafer to obtain thermal wave values and coordinates at multiple measurement points, generating a thermal wave distribution map; S3. Anneal the wafer that has completed the thermal wave test in step S2 to repair the lattice damage caused by ion implantation. Then, perform a resistance test on the repaired wafer to obtain the resistance values and coordinates of multiple measurement points and generate a resistance distribution map. S4. Compare and analyze the thermal wave distribution map and the resistance distribution map. By identifying the changing trend of abnormal areas in the two distribution maps, the root cause of the uniformity problem can be determined: if the thermal wave value and the resistance value change in opposite directions in the abnormal area, it is determined that the ion implantation dose is abnormal. If the thermal wave value and the resistance value change in the same direction in the abnormal area, it is determined that the ion implantation angle is abnormal.
2. The process analysis method for abnormal uniformity of ion implantation machine according to claim 1, characterized in that, The coordinates of the corresponding measurement points in the thermal wave distribution map generated in step S2 and the resistance distribution map generated in step S3 are consistent.
3. The process analysis method for abnormal uniformity of ion implantation machine according to claim 1 or 2, characterized in that, In step S4, the unidirectional change specifically means that the heat wave value and the resistance value are both high, or the heat wave value and the resistance value are both low.
4. The process analysis method for abnormal uniformity of ion implanter according to claim 3, characterized in that, In step S4, the reverse change specifically means: the heat wave value is high while the resistance value is low, or the heat wave value is low while the resistance value is high.
5. The process analysis method for abnormal uniformity of ion implantation machine according to claim 1 or 2, characterized in that, In step S2, the thermal wave value at the measurement point on the wafer surface during ion implantation is measured using a thermal wave probe.
6. The process analysis method for abnormal uniformity of ion implantation machine according to claim 1 or 2, characterized in that, In step S3, a four-probe tester is used to measure the resistance at measurement points on the wafer surface.
7. The process analysis method for abnormal uniformity of ion implanter according to claim 1 or 2, characterized in that, After step S4, a root cause report is output based on the comparison results to guide process adjustments.
8. A computer program product, comprising a computer program, characterized in that, The computer program is executed by the processor to perform the steps of the method as described in any one of claims 1-7.
9. A computer-readable storage medium having a computer program stored thereon, characterized in that, The computer program, when run by a processor, performs the steps of the method as described in any one of claims 1-7.
10. A process analysis system for abnormal uniformity in an ion implanter, comprising a memory and a processor interconnected, wherein the memory stores a computer program, characterized in that, The computer program, when run by a processor, performs the steps of the method as described in any one of claims 1-7.