TWI889555B - Electrical characteristics evaluation method, electrical characteristics evaluation device, and electrical characteristics evaluation system - Google Patents

Abstract

The purpose of the present disclosure is to evaluate the electrical characteristics of the entire semiconductor device using the results of evaluating the electrical characteristics of the element manufactured in the process of manufacturing the semiconductor device. The electrical characteristics evaluation method involved in the present disclosure receives the results of the electrical characteristics of the semiconductor element formed in the process of manufacturing the semiconductor device, reflects the second equivalent circuit of the semiconductor element on the first equivalent circuit of the semiconductor device, and simulates the electrical characteristics of the first equivalent circuit using the electrical characteristics of the semiconductor element (refer to FIG. 1).

Description

Electrical characteristics evaluation method, electrical characteristics evaluation device, and electrical characteristics evaluation system

The present disclosure relates to techniques for evaluating the electrical characteristics of semiconductor devices.

The following patent document 1 describes a charged particle beam device for estimating electrical characteristics such as capacitance characteristics of a sample. The same document describes the following matters: "The comparator 230 compares the calculation result stored in the estimated irradiation result storage unit 228 (i.e., the calculation result performed by the emission amount calculation unit 227) and the measured result stored in the electron beam irradiation result storage unit 229 (i.e., the measured result performed by the detector 219). Here, when an inconsistent comparison result is obtained by the comparator 230, the component parameter value in the calculation network connection table is updated by the calculation network connection table update unit 226, and the above-mentioned processing from the emission amount calculation unit 227 to the comparator 230 is performed again using the updated calculation network connection table. On the other hand, when a consistent comparison result is obtained by the comparator 230, the calculation net connection table update unit 226 stores the net connection table including the current component parameter value in the estimated net connection table storage unit 231 as the estimated net connection table" (paragraph 0034) [Prior technical literature] [Patent literature]

[Patent Document 1] Japanese Patent No. 7250642

[The problem that the invention wants to solve]

Patent Document 1 creates a network connection table that records the components of the equivalent circuit of a semiconductor device, and at the same time reflects the results of measuring electrical characteristics such as electrostatic capacitance in the network connection table. The measurement technology described in Patent Document 1 can measure the electrostatic capacitance of a semiconductor element formed inside the height direction of a sample, as described in, for example, FIG. 3A of the same document. The semiconductor element is manufactured in an intermediate process in the process of manufacturing the entire semiconductor device. That is, Patent Document 1 can be said to be a technology for measuring the electrical characteristics of an element manufactured in an intermediate process in the manufacture of a semiconductor device. Therefore, in the same document, the electrical characteristics reflected in the network connection table are also the electrical characteristics of the element manufactured in the intermediate process.

On the other hand, the electrical characteristics of the finished semiconductor device are measured by, for example, inputting an input signal by contacting a test probe with a measurement pad and measuring the response as an output signal. Alternatively, the electrical characteristics of the semiconductor device can be evaluated by simulating an equivalent circuit of the same semiconductor device using a SPICE simulator or the like and comparing the result with a reference value.

The SPICE simulator simulates the equivalent circuit of a semiconductor device based on the design data of the semiconductor device. This is effective as a method for evaluating the electrical characteristics of a finished semiconductor device. On the other hand, in the mid-process of manufacturing a semiconductor device, if the electrical characteristics of a component manufactured by the mid-process can be evaluated to see whether it is suitable for proceeding to the subsequent process (that is, whether the component as the mid-process product is a good product). Patent Document 1 can evaluate the electrical characteristics of such a component. However, the evaluation is not an evaluation of a finished semiconductor device, but an evaluation of the electrical characteristics of the component alone. In other words, in Patent Document 1, even if the electrical characteristics of the component are evaluated, how its electrical characteristics are reflected as the electrical characteristics of the finished semiconductor device is not fully considered in Patent Document 1.

This disclosure was created in view of the above-mentioned problems, and is intended to evaluate the electrical characteristics of the entire semiconductor device by using the results of evaluating the electrical characteristics of the components manufactured in the middle of the manufacturing process of the semiconductor device. [Means for solving the problem]

The electrical characteristics evaluation method disclosed herein receives the results of the electrical characteristics of a semiconductor element formed in the process of manufacturing a semiconductor device, reflects the second equivalent circuit of the semiconductor element on the first equivalent circuit of the semiconductor device, and uses the electrical characteristics of the semiconductor element to simulate the electrical characteristics of the first equivalent circuit. [Effect of the invention]

By using the electrical characteristics evaluation method disclosed herein, the electrical characteristics of the components manufactured in the middle of the manufacturing process of the semiconductor device can be used to evaluate the electrical characteristics of the entire semiconductor device. Other topics, structures, and advantages of the present disclosure can be understood by referring to the following embodiments.

[Background of this disclosure]

For the process management of semiconductor device manufacturing mid-process wafers, it is believed that the shape (CD value (average value, deviation), roughness value, etc.) or defect density specifications in each process can be estimated in a way that meets the electrical characteristics (including reliability and yield) specifications of the final process wafers of device manufacturing, so that good judgment can be made in each process.

On the other hand, in order to output the expected device behavior (electrical characteristics), as one of the device behavior principle verifications, what kind of layout requires what kind of process, there is an EDA (Electronic Design Automation) tool that simulates from design data to electrical characteristics output. By effectively using such EDA tools, it is possible to achieve early startup or stable operation of the manufacturing system of semiconductor devices. In addition, if defects can be detected in each process before moving on to the final process, feedback can be quickly given to the manufacturing process.

As the device structure becomes three-dimensional, the device structure becomes more complex and the holes in the Z direction become deeper. The risk of missing defects increases when only using CD SEM (Critical Dimension Scanning Electron Microscope) to manage the shape of each process, resulting in yield loss. Therefore, it is better to use another method with high sensitivity in the Z direction to determine the quality of each process. In particular, if the electrical characteristic quantity required by the electrical component can be evaluated, the previously described missing defects can be prevented.

A netlist is design data that represents the electrical components (assemblies) that make up a circuit such as a resistor, capacitor, inductor, transistor, and power supply. Such a netlist is sometimes used as input data for integrated circuit (IC) design simulation. IC design simulation is performed to analyze the netlist and determine how the circuit should operate. Semiconductor devices are manufactured through multiple manufacturing processes, and IC design simulation is used to evaluate the electrical characteristics of the device manufactured through multiple manufacturing processes.

Although the specifications of the components included in the net connection table provided for simulation are usually derived from the design data, if the electrical characteristics (specifications) that can be obtained by actual measurement in the completed process of the device can be used to simulate the electrical characteristics of the final process evaluation, the working quality of the semiconductor device caused by time changes or unexpected process changes can be evaluated before the final process of the semiconductor device. In this way, rapid feedback can be provided to the manufacturing process.

Hereinafter, a method of estimating electrical characteristics that can be obtained in a final process based on the setting of the specifications of a specific component that can be obtained in an intermediate process leading to the final process, a computer-based implementation method, a computer program, a non-temporary recording medium, a device, and a system will be described in detail using drawings.

As one aspect to achieve the above purpose, a method is proposed to convert "the output results of the resistance value or electrostatic capacitance value of the electrical components contained in the wafer measured in the process of device manufacturing" into "the electrical characteristics (I-V, Vth, frequency characteristics, etc.) output by the tester of the wafer in the final process of device manufacturing" and output the results as characteristics. If such a method is used, the output results of the electrical tester can be predicted based on the measured values in the process of manufacturing.

[Implementation of the present disclosure] FIG. 1 is a diagram showing an overview of an electrical characteristics evaluation system including a measurement tool capable of measuring the characteristics of electrical components contained in a semiconductor wafer in the process of device manufacturing. The system illustrated in FIG. 1 includes a design data storage medium 101 for storing layout data and/or a mark data format of an integrated circuit (for example, for storing GDSII (GDS2), GL1, OASIS, a mapping file, or other formats of a design data structure), an EDA tool 102, an electrical characteristics measurement device (electrical characteristics measurement tool) 103, and one or more computer systems 104. Furthermore, in the system illustrated in FIG. 1, other measurement devices 105 such as an optical inspection device OCD (Optical Critical Dimension), CD-SEM, EBI (Electron Beam Inspection) device, etc. may be connected. These devices (tools) are connected via bus 16 so that they can communicate with each other.

In the system shown in FIG. 1, one or more computer systems 104 are included, and the EDA tool 102 may include software for calculating the electrical characteristics of the circuit included in the simulation or semiconductor wafer described later, a storage medium for storing the software, and a computer system having one or more processors for implementing the software. It may also be possible to have a computer system installed in each device constituting the system, or to implement control of multiple devices with one workstation.

The electrical characteristic measuring device 103 includes a charged particle beam device (evaluation unit), which includes a beam column for detecting a beam (e.g., an electron beam) irradiating a sample, and a detector for detecting secondary electrons (SE) and/or backscattered electrons (BSE) obtained by irradiating the sample with the beam. In this embodiment, as an example of the electrical characteristic measuring device 103, although an example of deriving a resistance value or an electrostatic capacitance value of an electrical element based on brightness information (gray scale) obtained by the charged particle beam device is described, it is not limited to this, and even if output information is obtained based on a certain input, other derivation methods for obtaining a resistance value or an electrostatic capacitance value may be applied. In this case, a model defining the relationship between image information or detection signals and electrical characteristics may be stored in a specific storage medium, and the electrical characteristics may be derived using the model by one or more processors. The model may include a mathematical model, a database, a learned model that has been learned by machine learning, etc.

When the charged particle beam device is set as the electrical characteristic measuring device 103, it is possible to measure the brightness by irradiating a specific element on the sample (such as a plug visible on the wafer surface) with a point-like beam, electrically connecting to the specific element, and supplying a specific charge to the electrical element with one end grounded.

Even in the beam column of the charged particle beam device, it is possible to have a lens (for example, an electromagnetic lens) for focusing the beam into a point shape, or a deflector for adjusting the irradiation position of the beam. Furthermore, it is possible to have a deflector for eliminating the need for irradiating the beam to the target sample in a pulsed manner as described later. The deflector for eliminating the need for deflecting the beam is used to deflect the beam outward from the axis in order to cut off the beam from reaching the sample. It is possible to irradiate the sample with the beam in a pulsed manner by repeatedly turning on and off the deflection caused by the deflector for eliminating the need for deflecting. It is possible to have one or more computer systems (control devices) for controlling optical elements such as lenses in the charged particle beam device.

Furthermore, a storage medium storing an application program for evaluating the electrical characteristics of a circuit component connected to a terminal of a plug or the like to be irradiated with a beam based on the detector output may be built into the electrical characteristics measuring device 103.

Furthermore, the electrical characteristic measuring device 103 is provided with a charge supplying means for supplying a specific charge to a target object (object) to be measured for electrical characteristics. The charge supplying means includes, for example, a laser light source, and supplies a specific charge to the object by irradiating the object with a laser. In the state where the charge is supplied, the electrical characteristic evaluation described later is performed by irradiating a pulsed electron beam.

Figure 2 is a graph showing the change in brightness of SEM images relative to the change in cutoff time (time when the pulse beam is not irradiated) when the electron beam is irradiated in a pulsed manner. The left side of Figure 2 shows the change in brightness of electrostatic capacitor system defects relative to the change in cutoff time, and the right side of Figure 2 shows the change in brightness of resistor system defects relative to the change in cutoff time.

As shown in FIG2, the characteristics of the brightness change when the cutoff time is changed are different between the resistance system defect and the electrostatic capacitance system defect. Therefore, even if it is different in characteristics, it can be judged as an electrostatic capacitance system defect or a resistance system defect.

The defects of the electrostatic capacitor system tend to become more obvious as the cutoff time becomes longer. Even using such characteristics, it is possible to determine the defect type by the difference between the brightness in the area with a long cutoff time and the average value of the brightness registered in advance in the area with a long cutoff time (the average value of the brightness of different electrostatic capacitor defects). In this case, for example, if the difference exceeds a specific critical value, it is determined to be a defect of the electrostatic capacitor system, and if it is below the specific critical value, it is determined to be a defect of the resistor system.

Resistor system defects tend to become more distinct as the cutoff time becomes shorter. Even using such a feature, it is considered possible to determine the defect type based on the difference between the brightness in the area with a short cutoff time and the average value of the brightness registered in advance in the area with a short cutoff time (the average value of the brightness of different electrostatic capacitor defects). In this case, for example, if the difference exceeds a specific critical value, it is determined to be a resistor system defect, and if it is below the specific critical value, it is determined to be an electrostatic capacitor system defect.

Furthermore, even if the obtained curve is fitted to represent the relationship between the change in the cutoff time and the change in brightness for each defect type, the defect type can be classified according to the degree of consistency. In addition, it is also possible to prepare (memorize) multiple curves corresponding to multiple electrostatic capacitances and multiple curves corresponding to multiple resistances in advance, and estimate the electrostatic capacitance or resistance according to the degree of consistency.

Even if the resistance value and the electrostatic capacitance value are mathematical models, databases, or models learned with a data set of brightness information and electrical characteristic information, such as Equation 1, they can be derived by inputting brightness information. S represents brightness, C represents electrostatic capacitance, R represents resistance, Q represents charge accumulated in the sample by beam irradiation, Ti1 represents the first beam cutoff time of the pulse beam to the sample as the first beam irradiation condition, Ti2 represents the second beam cutoff time of the pulse beam to the sample as the second beam irradiation condition, and Tir represents the irradiation time of the beam.

The computer system that memorizes equation 1, a variation of equation 1, or a mathematical model equivalent to equation 1 derives electrical characteristics that C is electrostatic capacitance and R is resistance based on the difference information (ΔS) of brightness obtained when two pulse beams with different beam cutoff times are irradiated. This method is only one example, and other methods that derive electrical characteristics such as the above may be used, such as using measurements that can model the relationship with electrical characteristics or receiving information output from an inspection tool.

The EDA tool 102 is software for designing or supporting semiconductor devices, or for automatically analyzing the operation of semiconductor devices, or one or more computer systems for implementing the software.

The EDA tool 102 automatically implements support for semiconductor device design based on input of semiconductor device design data, product media, specifications, etc. The EDA process using the EDA tool 102 includes, for example, system design, logic design, function verification, data synthesis and design for testing, netlist verification, design planning, physical implementation, analysis and extraction of circuit functions at the layout level, physical verification, change (adjustment) of layout geometry, and preparation of mask data.

Even the EDA process of the EDA tool 102 may include processing for estimating the electrical output characteristics of semiconductor elements in the final stage of the semiconductor manufacturing process (pre-process). Furthermore, not only the EDA process but also simulation may be performed in the manufacturing process of semiconductor devices, and feedback and/or feedforward may be performed on the semiconductor manufacturing process in response to the simulation results. In this embodiment, as described later, even in the middle of the manufacturing process of a semiconductor device, for example, the electrical characteristics of a small-scale circuit that can be obtained through the mid-stage process may be input and the electrical output characteristics of the semiconductor elements in the final stage may be obtained by simulating them.

In order to perform the above-mentioned simulation, the EDA tool 102 obtains information about the circuit generated from the bare die to the final process and the electrical characteristic information of the small-scale circuit in the current process. Even if the EDA tool 102 is provided with software or a storage medium inside or outside the storage application that can perform the simulation by replacing part of the information of the net connection table generated from the design data with the information obtained by the electrical characteristic measurement device 103 to generate a part of the measured value, and can perform the above-mentioned simulation based on the net connection table, etc., and can perform the simulation.

FIG3 is a schematic side cross-sectional view showing the relationship between the first equivalent circuit 310 and the second equivalent circuit 320. The first equivalent circuit 310 is a circuit to be evaluated by an electrical tester for a "wafer in the final process of device manufacturing". The second equivalent circuit 320 is a circuit or an electrical component to be evaluated by an electrical characteristic measurement device 103 for a "wafer in the middle process of device manufacturing".

Semiconductor devices include multiple layers of electrical components that constitute circuits, and are formed into multi-layer structures through multiple manufacturing processes on unprocessed wafers (bare crystals). On semiconductor devices that have reached the final process, pads 311 (input) and pads 312 (output) are sometimes provided, which can measure electrical characteristics by contact with a probe, etc. By monitoring the output signal (voltage) when a specific input signal (current) is supplied to the pad, the working quality of the semiconductor device or the suitability of the manufacturing process can be judged.

The electrical components 321 or 322 are formed inside the semiconductor device in the height direction. These electrical components are manufactured in the middle of the semiconductor device manufacturing process. When the test probe is brought into contact with the pads 311 and 312 to measure the output signal, the electrical characteristics of the entire semiconductor device including these internal electrical components are measured. On the other hand, when the electrical characteristics of the electrical components 321 or 322 are measured, the electrical characteristics are measured using the electrical characteristics measuring device 103 in the middle of the semiconductor device manufacturing process (that is, at the stage of forming the electrical components 321 or 322 in the stacking process).

When the electrical characteristic measuring device 103 measures the electrical characteristics of the electrical element 321 or 322, the electrical characteristics are obtained by grounding the elements and irradiating the elements with a charged particle beam, as described in Patent Document 1. Therefore, the second equivalent circuit is also described by grounding the elements. In this regard, since the semiconductor device is not limited to being measured by a tester in a grounded state, the first equivalent circuit may not include grounding.

Fig. 4 is a diagram showing an output signal obtained from pad 312 when a specific signal is supplied to pad 311. The upper part of Fig. 4 shows an output signal when the circuit connected to the pad is normal. The lower part of Fig. 4 shows an example of an output signal when there is some abnormality in the circuit.

If such an output signal can be obtained before the final process of the device manufacturing process, feedback can be quickly provided to the semiconductor manufacturing process. In this embodiment, an example of deriving the output signal shown in FIG. 4 by calculation (simulation) rather than actual measurement is described.

FIG. 5 is a flow chart showing a part of a manufacturing process of a semiconductor device including a design process of the semiconductor device.

In step S501: in the EDA process, the EDA tool 102 receives design data in a format for storing design data structures, schematic data for presenting the configuration or connection of components constituting a circuit on a layout, and a PDK (Process Design File) as a design information file used when performing circuit design in a specific semiconductor process.

Step S502: One or more computer systems (processors) included in the EDA tool 102 generate three-dimensional structure (3D Layout) data of the semiconductor device according to the received data.

Steps S503-S504: One or more computer systems create a process flow based on the generated 3D Layout data and simultaneously generate an equivalent circuit for subsequent simulation.

Since the manufacturing process and its coordinates that are the measurement objects of the electrical characteristic measurement device 103 become clear through step S505: generation of the process flow or equivalent circuit, the electrical characteristic measurement device 103 can create a measurement flow based on the process flow data.

Step S506: In the EDA process, one or more computer systems create a device model used in the circuit analysis in S507 described later. The device model is, for example, an analytical expression, and in the model creation, the analytical expression and model parameters such as variables and constants contained in the analytical expression are created and set.

Step S507: After one or more computer systems generate an equivalent circuit for the entire circuit including the layer of the measurement object, they perform circuit simulation such as SPICE (Simulation Program with Integrated Circuit Emphasis) based on the equivalent circuit. Circuit simulation is performed in the order of circuit description, circuit analysis, and analysis result output. Here, the circuit diagram input by the circuit diagram editor is converted into a net connection table, which is handed over to the analysis engine to automatically perform simulation.

Step S508: One or more computer systems calculate electrical characteristics through circuit simulation, and store the derived electrical characteristics information in a specific storage medium. One or more computer systems determine whether the circuit design is appropriate based on the appropriateness of the derived electrical characteristics, and update the design data as needed.

Through the semiconductor design process described above, the semiconductor device manufacturing (mass production) stage is moved to. In the mass production process, it is better to appropriately evaluate the process changes of the semiconductor device and provide feedback/feedback to the manufacturing process. Therefore, in this embodiment, an example of implementing engineering management in the mass production stage using the simulation model generated in the EDA process is explained.

In this embodiment, although an example is given of inputting data related to circuit simulation, model, equivalent circuit, etc. generated by an EDA process into a computer system that stores an EDA tool or a specific program, the present invention is not limited to this. Even in a mass production process, the circuit simulation, model, equivalent circuit, etc. may be recreated using an EDA tool or other computer system, and the processing described later may be performed based on the obtained equivalent circuit, etc.

In step S509: in the measurement process of the semiconductor device included in the mass production process, measurement using the electrical characteristic measurement device 103 is performed. In the measurement process illustrated in FIG5 , first, the electrical characteristic output information obtained by the EDA process is received. In the EDA process, in order to achieve proper design, the electrical characteristics of the device in a normal state are obtained by simulation, so reference information is prepared based on the data. Here, the electrical characteristics obtained by simulation are received, and the electrical characteristics are set to a reference range (normal range) that is a normal value. The information used as reference information is not limited to that obtained by simulation, and may be, for example, an actual measured value at a reference point or other appropriate values.

Step S510: After the above preparations, the semiconductor wafers manufactured by the mass production process are measured. Then, the electrical characteristics are measured by irradiating the electrical characteristics of the evaluation object or the terminal (plug, etc.) connected to the evaluation object with a beam.

Step S511: One or more computer systems built into the EDA tool 102 or the electrical characteristic measuring device 103, or other computer systems (e.g., computer system 104) that are communicatively connected to the electrical characteristic measuring device 103, receive the electrical characteristic measurement results of the electrical components in the middle of the manufacturing process of the semiconductor device, such as the capacitance value, the resistance value, etc. The computer system may obtain the electrical characteristic information through other computer systems, or receive the output of the detector built into the electrical characteristic measuring device 103, calculate the electrical characteristic information based on the output of the detector, and perform the processing described below.

Step S512: The EDA tool 102 etc. receives the device model provided for circuit simulation. Although the device model is described as being generated by the EDA process, it is not limited thereto, and a device model with updated parameters may be generated by mass production engineering using other measurement results etc.

Step S513: The EDA tool 102 etc. updates the device model by inputting the measurement results of the specific components into the device model. For example, the electrical characteristics of the second equivalent circuit contained in the first equivalent circuit at this time are replaced with the electrical characteristics measurement values in S510. At this time, a net connection table equivalent to the first equivalent circuit and a GUI (Graphical User Interface) screen that is displayed together with the measurement results (measurement results of the second equivalent circuit) of the electrical characteristics measurement device 103 are prepared. By being able to selectively input any result among the multiple electrical characteristics measurement results obtained in each manufacturing process, it is possible to implement a simulation of the working quality of the electrical components that can be measured in different manufacturing processes. The GUI can be provided by, for example, the computer system 104.

Steps S514-S515: The EDA tool 102 etc. performs SPICE simulation (S514) based on the device model partially input with the measured values in S513, and outputs electrical characteristics (I-V, Vth, frequency characteristics, etc.). The output electrical characteristics are derived from the device model after the parameter update using the measured values that can be obtained in the middle of the manufacturing process of the semiconductor device. Therefore, the suitability of the device in the final process can be judged before the final process.

Steps S516 to S518: The output electrical characteristics are compared with the reference information obtained in step S509 (S516). Based on the comparison, defect determination is performed (S517). The defect determination result is fed back to the manufacturing process (S518).

FIG6 is a process flow chart of the electrical characteristics evaluation system. The EDA tool 102, the electrical characteristics measurement device 103 and the computer system (including the computer system 104) that controls the flow chart illustrated in FIG5 can constitute an electrical characteristics evaluation system for evaluating the electrical characteristics of a semiconductor device. FIG6 is equivalent to visually rewriting the process sequence of the flow chart of FIG5.

EDA tool 102 receives design data, schematic data, PDK, etc. (S501), and uses the data to create 3D Layout data (S502). EDA tool 102 creates a process flow based on the 3D Layout data (S503). EDA tool 102 specifies the measurement object layer and measurement object of a semiconductor component, and simultaneously creates its equivalent circuit (S504-S505). The measurement object referred to here is the second equivalent circuit illustrated in FIG. 3. EDA tool 102 creates a SPICE simulation model of the equivalent circuit of the final project (equivalent to the finished product of the semiconductor device) (S506).

On the other hand, the electrical characteristic measuring device 103 measures the electrical characteristics of the semiconductor element (equivalent to the second equivalent circuit) (S510), and returns the result to the EDA tool 102 (S513).

The EDA tool 102 reflects the electrical characteristics of the semiconductor element (second equivalent circuit) measured by the electrical characteristics measuring device 103 to the SPICE simulation model (S513). The EDA tool 102 uses the reflection result to calculate the electrical characteristics by simulating the entire semiconductor device (i.e., the first equivalent circuit) (S514) and outputs the result (S515). The electrical characteristics measuring device 103 determines whether the measured part has defects based on the result (S516-S517).

FIG7 is a process flow chart of the electrical characteristic evaluation system. Although FIG6 shows the electrical characteristic measurement device 103 and the computer system 104 as a whole, FIG7 shows them separately. The electrical characteristic measurement device 103 creates an SEM image of the semiconductor element by irradiating the semiconductor element being manufactured in the intermediate process with a charged particle beam. The computer system 104 creates its measurement recipe or a network connection table of the second equivalent circuit, and uses these to control the process of obtaining the SEM image. The computer system 104 uses the SEM image and the network connection table of the second equivalent circuit to calculate the electrical characteristics (resistance value or electrostatic capacitance value) of the second equivalent circuit, and outputs the result to the EDA tool 102.

The EDA tool 102 reflects the electrical characteristics of the second equivalent circuit in the net connection table of the first equivalent circuit, and uses this to perform SPICE simulation. In this way, the result of measuring the electrical characteristics of the second equivalent circuit (that is, the semiconductor device made in the process of manufacturing) by the electrical characteristic measuring device 103 can be obtained, and the electrical characteristics of the first equivalent circuit (that is, the entire semiconductor device) can be simulated by the EDA tool 102. The judgment conditions for whether the first equivalent circuit has defects are prepared in advance in the manufacturing process. By providing this to the computer system 104, the computer system 104 can judge whether there are defects based on the results of SPICE simulation. The computer system 104 outputs its judgment results, and can feedback the main causes of defects to the manufacturing process as needed.

FIG8 is a process flow chart of the electrical characteristic evaluation system. In FIG7, the process flow of measuring electrical characteristics is shown for the measurement object of a specific measurement object layer. That is, FIG7 is used to obtain the measurement result only for the specified position. In contrast, in FIG8, a more comprehensive inspection is performed to check whether the object area of the specified object layer is a good product or a defective product. Therefore, since the electrical characteristic measurement device 103 operates as an electrical characteristic inspection device, it is recorded as such even in FIG8.

The computer system 104 measures the electrical characteristics of the designated area and determines whether the designated area is a good product or a defective product based on the results. The EDA tool 102 obtains the electrical characteristics of the designated area and simulates the electrical characteristics of the first equivalent circuit. The computer system 104 determines whether the first equivalent circuit is a good product or a defective product based on the simulation results.

FIG9 is an example of a user interface provided by the electrical characteristics evaluation system. The user interface can be provided as a GUI in, for example, a computer system 104. The user selects any one or more of the components included in the first equivalent circuit on the UI to instruct the simulation to be performed. The EDA tool 102 uses the selected components and the results of the electrical characteristics of the electrical components measured in advance by the electrical characteristics measurement device 103 to perform the simulation. The electrical characteristics of the electrical components may also be presented together. The UI may also present the simulation results together with the Pass/Fail or good/bad product judgment results illustrated in FIG7 .

[Variations of the present disclosure] In the above implementation, when the EDA tool 102 captures the results of the electrical characteristics of the electrical component 321, etc. measured by the electrical characteristics measuring device 103, the electrical characteristics measuring device 103 outputs the electrical characteristics of the electrical component 321, etc. and the network connection table of the second equivalent circuit in a data format that can be captured by the EDA tool 102. The EDA tool 102 integrates these into the network connection table of the first equivalent circuit. The specific data format or integration processing can be appropriately set according to the specifications of the EDA tool 102. Alternatively, even if the electrical characteristics measuring device 103 outputs a general data format such as test data, the process of converting the data format is placed between the electrical characteristics measuring device 103 and the EDA tool 102 so that the two can exchange data. In either case, the electrical characteristics measuring device 103 outputs the electrical characteristics of the electrical component 321 and the network connection table of the second equivalent circuit in the form of data that can be ultimately captured by the EDA tool 102.

In the above implementation, the processing flow described in FIG. 5 to FIG. 8 can be realized by executing a program installed with the process on a computer system (e.g., computer system 104). The program may be composed of a single program module or may be divided into a plurality of program modules. Each program module may be configured on the same computer system or any program module may be distributed on two or more computer systems.

In the above embodiments, the computer system 104 or a computer system equivalent thereto may be configured for each of the EDA tool 102, the electrical characteristic measuring device 103, and the measuring device 105, or a single computer system may control any one or more of them.

In the above embodiment, the electrical characteristic measuring device 103 is described as measuring or inspecting the electrical characteristics of the semiconductor element being manufactured in the process of manufacturing the semiconductor device in accordance with the purpose of the electrical characteristic evaluation system. The implementation of the electrical characteristic measuring device 103 is not limited to this, and the general evaluation of the electrical characteristics of the semiconductor device can be implemented. The evaluation referred to here includes any process for obtaining the physical state of the semiconductor device in addition to measurement and inspection. Therefore, the electrical characteristic measuring device 103 has a function as an electrical characteristic evaluation device in general.

101: Design data storage medium 102: EDA tool 103: Electrical characteristics measurement device 104: Computer system 105: Measurement device

[FIG. 1] is a diagram showing an overview of an electrical characteristics evaluation system including a measurement tool capable of measuring the characteristics of an electrical element included in a semiconductor wafer in the process of device manufacturing. [FIG. 2] is a graph showing the change in brightness of an SEM image relative to the change in the cutoff time (time when the pulse beam is not irradiated) when an electron beam is irradiated in a pulsed manner. [FIG. 3] is a schematic side cross-sectional diagram showing the relationship between the first equivalent circuit 310 and the second equivalent circuit 320. [FIG. 4] is a diagram showing an output signal obtained from a pad 312 when a specific signal is supplied to a pad 311. [FIG. 5] is a flow chart showing a part of a manufacturing process of a semiconductor device including a design process of a semiconductor device. [FIG. 6] is a process flow chart of the electrical characteristics evaluation system. [Figure 7] is a process flow chart of the electrical characteristics evaluation system. [Figure 8] is a process flow chart of the electrical characteristics evaluation system. [Figure 9] is an example of a user interface provided by the electrical characteristics evaluation system.

101: Design data storage media

102:EDA tools

103: Electrical characteristics measurement device

104: Computer system

105: Measuring device

Claims (10)

An electrical characteristic evaluation method, which is an electrical characteristic evaluation method for evaluating the electrical characteristics of a semiconductor device, comprises: A step of obtaining a first list, wherein the first list records the constituent elements of the first equivalent circuit of the semiconductor device included in the semiconductor element formed in the intermediate process of the manufacturing process of manufacturing the semiconductor device; A step of simulating the electrical characteristics of the first equivalent circuit using the first list; and A step of evaluating the electrical characteristics of the semiconductor device based on the result of the simulation, The simulation step further comprises a step of obtaining a second list, wherein the second list records the constituent elements of the second equivalent circuit of the semiconductor element formed in the intermediate process, The simulation step further includes: obtaining a result of evaluating the electrical characteristics of the semiconductor element using the second equivalent circuit. In the simulation step, the second equivalent circuit recorded in the second list is integrated into the first equivalent circuit recorded in the first list. In the simulation step, the simulation is performed by using the electrical characteristics of the semiconductor element to simulate the electrical characteristics of the first equivalent circuit including the second equivalent circuit. The electrical characteristics evaluation method as described in claim 1, wherein the result of evaluating the electrical characteristics of the semiconductor element is evaluated by detecting secondary charged particles generated by irradiating the semiconductor element with a charged particle beam. The electrical characteristics evaluation method as described in claim 1, wherein the first equivalent circuit does not have a ground potential, and the second equivalent circuit has a ground potential connected to the semiconductor element. The electrical characteristic evaluation method as described in claim 1, wherein the electrical characteristic of the semiconductor element is at least one of the resistance of the semiconductor element or the electrostatic capacitance of the semiconductor element, and in the simulation step, the simulation is performed using the resistance of the semiconductor element or the electrostatic capacitance of the semiconductor element obtained in the step of obtaining the electrical characteristic of the semiconductor element. The electrical characteristics evaluation method as described in claim 1, wherein the manufacturing process is configured to form the semiconductor element by stacking a plurality of layers in the height direction of the semiconductor device, and in the simulation step, the electrical characteristics of the first equivalent circuit are simulated by simulating the response obtained by inputting an electrical signal from the surface of the semiconductor device. The electrical characteristics evaluation method as described in claim 5, wherein the semiconductor device has an input pad for inputting the electrical signal from the tester to the semiconductor device, and an output pad for outputting the response from the semiconductor device to the tester, and the electrical characteristics evaluation method further has a step of evaluating the electrical characteristics of the semiconductor device by comparing the response measured using the tester with the result of the simulation. The electrical characteristics evaluation method as described in claim 1, wherein the first equivalent circuit is an equivalent circuit of a final product device manufactured in the manufacturing process, in the simulation step, the second equivalent circuit is integrated into the first equivalent circuit recording the equivalent circuit of the final product device, in the simulation step, the electrical characteristics of the final product device including the semiconductor element are simulated. The electrical characteristics evaluation method as described in claim 1, wherein the electrical characteristics evaluation method further comprises the step of presenting a user interface of a component whose electrical characteristics are simulated in the simulation step, and in the simulation step, the electrical characteristics of the component specified in the user interface are simulated. An electrical characteristic evaluation device for evaluating the electrical characteristics of a semiconductor device, comprising: an evaluation unit for evaluating the electrical characteristics of a semiconductor element formed in an intermediate process of a manufacturing process for manufacturing the semiconductor device; and a computer system for controlling the evaluation unit, the semiconductor device is configured to be represented by a first list recording components constituting a first equivalent circuit including the semiconductor element, the computer system obtains a second list recording components constituting a second equivalent circuit of the semiconductor element formed in the intermediate process, the computer system uses the second equivalent circuit to evaluate the electrical characteristics of the semiconductor element through the evaluation unit, The computer system outputs the evaluation results of the electrical characteristics of the second table and the semiconductor element in a form that can integrate the second equivalent circuit recorded in the second table into the first equivalent circuit recorded in the first table. An electrical characteristic evaluation system, which is an electrical characteristic evaluation system for evaluating the electrical characteristics of a semiconductor device, comprising: The electrical characteristic evaluation device as described in claim 9; A simulation tool for simulating the electrical characteristics of the first equivalent circuit using the first list, The simulation tool obtains the second list from the electrical characteristic evaluation device and obtains the evaluation result of the electrical characteristics of the semiconductor element from the electrical characteristic evaluation device, The simulation tool integrates the second equivalent circuit described in the second list into the first equivalent circuit described in the first list, The simulation tool performs the simulation using the electrical characteristics of the semiconductor element, and simulates the electrical characteristics of the first equivalent circuit including the second equivalent circuit.

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