JPH08194730A - Process simulation device - Google Patents

Abstract

PURPOSE: To provide a process simulation device which can analyze the impurity concentration distribution of a microfabricated semiconductor element in short analysis time. CONSTITUTION: A simple process simulator 4 which can repetitively execute simulation while input (process) data 3 is corrected and a highly precise process simulator 101 for obtaining a highly precise result 5 based on a process decided by the simulator 4 and for obtaining element characteristic (prediction) data 106 by a device simulator 105 are combined. A controller 2 controls them by adjusting them to the need of a user and two/three-dimensional process simulation is executed. Process simulation is repetitively executed for many times while the input process is corrected, and the appropriate process can be decided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor process simulation apparatus, and more particularly to an apparatus for simulating a process of forming a semiconductor element on a substrate in two dimensions or three dimensions (hereinafter referred to as "2/3 dimensions").

[0002]

2. Description of the Related Art A simulation of a semiconductor device manufacturing process has been used for designing a semiconductor device and has been useful for shortening a manufacturing period. The process simulation feeds back the output to the input, corrects the input process data based on the output analysis result, and obtains an input process that gives an appropriate output result, until the satisfactory result is obtained. It is used repeatedly. In addition, the process simulation is used in such a manner for fitting various parameters in the process called parameter fitting. For this reason, one-dimensional process simulators have been used that require higher execution speed than accuracy.

On the other hand, with the miniaturization of semiconductor elements, the two-dimensional effect and the three-dimensional effect of the element have begun to appear, and the simple one-dimensional approximation is no longer valid, and more complicated two-dimensional and three-dimensional simulators have appeared. I've been In order to realize the high speed, the process simulator that requires high speed is analyzed using a one-dimensional process simulator instead of actually analyzing the two or three dimensions, and the result is simply expanded to two or three dimensions. Method is used.

Further, as shown in Japanese Patent Application No. 5-292979, the one-dimensional cumulative diffusion length distribution is expanded to three-dimensional, so that the one-dimensional impurity concentration distribution is simply turned into three-dimensional. There is also a method of obtaining a three-dimensional impurity concentration distribution more accurately than the method.

FIG. 6 shows an example of a conventional process simulation apparatus. FIG. 6 shows a process simulation device 6, input data 3 to it, input device 102, output data 5 from it, display device 103, and output device 104.
Consists of The output data 5 of the process simulation device 6 is composed of two-dimensional and three-dimensional impurity concentration distribution data and the like, and also serves as input data to the device simulator 105. When the output data 5 is input to the device simulator 105 and a device simulation is performed, element characteristic data 106 and the like are output.
In some cases, the element characteristic data 106 that is the result of the device simulation is input to the circuit simulator 107, and the circuit simulation is also performed. The process simulation device 6 includes a pseudo two / three-dimensional high-speed simple process simulator 4.

FIG. 7 shows an example of another conventional process simulation apparatus. FIG. 7 shows a process simulation device 7, input data 3 to the process simulation device 3, and an input device 10.
2, output data 5, a display device 103, and an output device 104. The output data 5 of the process simulation device 7 is composed of two-dimensional and three-dimensional impurity concentration distribution data and the like.
It also serves as input data to 05. When the output data 5 is input to the device simulator 105 and a device simulation is performed, element characteristic data 106 and the like are output. In some cases, the device characteristic data 106 that is the result of this device simulation is used as the circuit simulator 1.
It is input to 07, and circuit simulation is also performed. The process simulation device 7 includes a two / three-dimensional high-precision process simulator 101.

[0007]

With the miniaturization of semiconductor devices, the conventional semiconductor scaling rule is becoming difficult to hold, and it is becoming difficult to predict the device characteristics. Therefore, a highly accurate process simulator has been demanded. However, the conventional process simulator centered on one-dimensional analysis is simple and fast, but has a problem in accuracy, and is not sufficient for predicting the characteristics of a miniaturized device. On the contrary, the two- or three-dimensional high-accuracy process simulator that appeared there is conversely sufficient in terms of accuracy, but considering the usage required for process simulation, there is a problem in its execution speed, and device characteristic prediction can be used for device design. It is still insufficient to use. Therefore, future process simulators must solve the conflicting problems of high precision and high speed execution. Otherwise, even the significance of the existence of a process simulator could be jeopardized.

An object of the present invention is that the analysis time is short enough to be used such that the output is fed back to the input and repeatedly executed until a satisfactory result is obtained, and it is sufficient as a characteristic prediction of a miniaturized semiconductor device. It is an object of the present invention to provide a two / three-dimensional process simulation device capable of performing a two / three-dimensional impurity concentration distribution analysis with a high degree of accuracy that can be used for.

[0009]

To achieve the above object, the process simulation apparatus of the present invention, as shown in FIG. 1, (A) determines a suitable process for obtaining desired device characteristics. In order to obtain a highly reliable element characteristic prediction by obtaining a highly accurate analysis result based on the high-speed simple simulator 4 that can be repeatedly executed while modifying the input process 3 and the process 3 determined there. In combination with the high-precision simulator 101, the controller 2 that determines that the input process 3 is appropriate from the analysis result obtained by the simple simulator 4 and switches the processing to the high-precision simulator 101 is provided. Perform process simulation of.

Further, (B) while changing the process data 3 to be input, the controller 2 automatically controls the high-speed simple simulator 4 to be repeatedly executed a plurality of times until an appropriate input process is obtained.

Further, (C) the user determines from the analysis result that the input process is appropriate based on the analysis result obtained by the high-speed simple simulator 4, and the process is repeated a plurality of times by the high-speed simple simulator 4. Whether to switch the processing to the high-precision simulator 101 is externally input and controlled.

[0012]

The simple process simulator cannot obtain a sufficient two- or three-dimensional impurity concentration distribution by itself, but it can obtain a sufficient rough tendency. The execution time for the analysis is basically a method of expanding the one-dimensional process simulation result into two or three dimensions, and therefore does not significantly increase as compared with the one-dimensional process simulator. Therefore, in the present invention, while correcting the input process by the controller, the process simulation is repeatedly executed by using this simple process simulator. From the analysis result obtained as a result, it is possible to determine an appropriate input process for obtaining a desired device characteristic, and it is possible to avoid an enormous execution time for that.

However, since the impurity concentration distribution obtained here is insufficient in terms of accuracy, the present invention uses a highly accurate 2 / 3D process simulator with the process determined here as input data. Process simulation. Since this analysis result has high accuracy, it can be confirmed whether the initially expected impurity concentration distribution can be obtained by the determined process. The execution time for the analysis is
It is much larger than the simple process simulation, but since it is an execution for confirming the decision process, it need not be repeated many times. Therefore, according to the present invention in which a high-speed simple 2 / 3D process simulator and a high-precision 2 / 3D process simulator are combined and controlled by a controller, the time of the process simulation performed to finally obtain a highly accurate impurity concentration distribution. However, it becomes possible to suppress the enormous increase.

[0014]

1 shows an embodiment of a process simulation apparatus according to the present invention. FIG. 1 shows a process simulation device 1, input data 3 to the process simulation device 10, and an input device 10.
2, output data 5, a display device 103, and an output device 104. The output data 5 of the process simulation apparatus 1 is composed of two-dimensional and three-dimensional impurity concentration distribution data and the like.
It also serves as input data to 05. When the output data 5 is input to the device simulator 105 and a device simulation is performed, element characteristic data 106 and the like are output. In some cases, the device characteristic data 106 that is the result of this device simulation is used as the circuit simulator 1.
It is input to 07, and circuit simulation is also performed.

The process simulation device 1 comprises a pseudo two / three-dimensional high-speed simple process simulator 4, a two / three-dimensional high-precision process simulator 101, and a controller 2 for controlling them.

The input data 3 is input to the pseudo two / three-dimensional high-speed simple process simulator 4 and the two / three-dimensional high-accuracy process simulator 101, and consists of information necessary for executing a process simulation such as a process flow sequence.

The input device 102 is composed of a keyboard and a mouse for inputting a command from the user to the process simulation device 1, and the command from the user is input to the controller 2.
Is input to.

The display device 103 displays information for controlling the process simulation device 1, analysis results of the pseudo two / three-dimensional high-speed simple process simulator 4, two / three-dimensional high-precision process simulator 101, progress, execution status, etc. Display to the user and provide information for input from the user. According to the input from the user, the output device 104 provides the user with the analysis result of the pseudo-two / three-dimensional high-speed simple process simulator 4 and the two-third-dimensional high-precision process simulator 101, the progress, the execution status, etc. in the same manner as the display device 103. Output.

The controller 2 controls the execution of the pseudo two / three-dimensional high-speed simple process simulator 4 and the two / three-dimensional high-accuracy process simulator 101 in accordance with a user's instruction input from the input device 102.

The pseudo-two / three-dimensional high-speed simple process simulator 4 repeats the high-speed process simulation many times while changing the content of the input data 3 so that the process of the input data 3 satisfies the user's request and is satisfied. It is executed until a possible execution result is obtained.

Two / three-dimensional high-precision process simulator 1
01 performs a highly accurate process simulation based on the input data 3 obtained there, and calculates a highly accurate impurity concentration distribution so that highly accurate device characteristics can be obtained in a later device simulation.

FIG. 2 shows a flowchart of the processing of the controller 2 based on the user's control command input. When the process starts (200), the process first branches depending on whether or not the user wants to confirm the validity of the input data 3 (201). If confirmation is required, the pseudo two / three-dimensional high-speed simple process simulator 4 is used. A process simulation is performed (202). If not, the process branches depending on whether or not it is desired to obtain a simulation result quickly (203) even if it is not highly accurate. If it is desired to obtain a result quickly, it branches to the previous 202, and if not so, it is 2 / 3D. High precision process simulator 1
Run the process simulation using 01 (2
04).

After the simulation of 202, the process branches depending on whether or not the analysis result is satisfied (205). If the analysis result is not satisfied, the input data 3 is corrected (206) and the process returns to 201 again to obtain the analysis result. This loop 201 → 202 → 205 → 206 → 201 is repeated until it is satisfied.

If the analysis results are satisfactory, whether or not to re-execute a more accurate process simulation (20
When the process branches in 7) and is re-executed, the process is branched to the process simulation execution (204) using the above-described 2 / 3-dimensional high-precision process simulator 101. When not re-executed, the simulation of 204 is not executed, and the process branches after that.

Therefore, based on the result of the process simulation obtained at that time, the process branches depending on whether or not the device simulation is executed (208), and when it is executed, the output result of the process simulation is used as the input data for the device simulation. (209) and the process ends (210). If not to be executed, the process is terminated as it is (210).

Among these series of processing, is the analysis result of executing the process simulation using the pseudo two / three-dimensional high-speed simple process simulator 4 satisfied (20
The determination reference value may be set in the controller 2 from the beginning so that the determination of the process branch of 5) can be automatically performed. In addition, the result is displayed on the display device 103 and the output device 104.
It is also possible to notify manually to the user, let the user decide, and manually input the instruction for control to the controller 2 from the outside by the user with the input device 102.

FIG. 3 shows a process simulation apparatus 1
3 shows the internal structure of input data 3 for the input. Input data 3 is
A process flow sequence 301 that is the basis of the process simulation, a mask layout 302 that shows the shape and the spatial distribution of the process, and a divided mesh 30 for analysis.
It consists of 3.

FIG. 4 shows the internal structure of the pseudo two / three-dimensional high-speed simple process simulator 4. According to the control command of the controller 2, the input data 3 is converted into a plurality of one-dimensional process simulation input data 402 by the one-dimensional process simulation data generation function 401 based on the impurity species added in the mask layout 302 and the process flow sequence 301. , 403, 404 are decomposed and synthesized. Furthermore, the function of 401 also generates the 2 / 3-dimensional control data 405 based on the mask layout 302, the added impurity species, and the divided mesh 303 for analysis.

A plurality of one-dimensional process simulation input data 402, 403, 404 are input to a one-dimensional process simulation controller 406, and this controller 406 controls the 2 / 3D control data 4.
Based on the information of 05, 402, 403 and 404 are input to the one-dimensional process simulator 407. As a result, the one-dimensional process simulator 407 outputs a plurality of one-dimensional process simulation results 408, 409, 410.

The plurality of one-dimensional process simulation results 408, 409, 410 are input to the 2 / 3-dimensional impurity concentration distribution generating function 411. The function of this 411 is a plurality of one-dimensional impurity concentration distributions 408, 40 based on the information of the 2 / 3-dimensionalized control data 405.
A two- or three-dimensional impurity concentration distribution is generated from 9,410. In this way, the pseudo two / three-dimensional high-speed simple process simulator 4 executes the two / three-dimensional process simulation at high speed by expanding the one-dimensional process simulation result to the two / three-dimensional.

FIG. 5 shows the internal structure of the output data 5 from the process simulation apparatus 1. Output data 5 is
It is composed of two / three-dimensional impurity concentration distribution data 501, two / three-dimensional carrier concentration distribution data 502 which are the result of the process simulation, divided mesh data 503 used for executing the process simulation, and mask layout data 504. These also serve as input data to the device simulator 105 and are used to execute the device simulation.

[0032]

According to the present invention, an analysis time is short enough to be used such that an output is fed back to an input and repeatedly executed until a satisfactory result is obtained, and as a characteristic prediction of a miniaturized semiconductor element. It is possible to realize a two / three-dimensional process simulation apparatus capable of performing impurity concentration distribution analysis with high accuracy so that it can be sufficiently used.

[Brief description of drawings]

FIG. 1 is a block diagram of a process simulation apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart of processing of a controller according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram of the inside of input data to the process simulation apparatus according to the embodiment of the present invention.

FIG. 4 is an internal block diagram of a pseudo two / three-dimensional simple process simulator according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram of the inside of output data according to an embodiment of the present invention.

FIG. 6 is a block diagram of a system as an example of a conventional process simulation apparatus.

FIG. 7 is a block diagram of a system of an example of a conventional process simulation apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Process simulation device, 2 ... Controller, 3 ... Input data, 4 ... Pseudo two / three-dimensional high-speed simple process simulator, 5 ... Output data, 101 ... Two / three-dimensional high-precision process simulator, 105 ... Device simulator, 106 ... Element characteristic data, 107 ... Circuit simulator.

Front page continuation (72) Inventor Goichi Yokomizo 1-280, Higashi Koikeku, Kokubunji, Tokyo, Central Research Laboratory, Hitachi Ltd. (72) Inventor, Megumi Kawakami 1-280, Higashi Koikeku, Kokubunji, Tokyo Hitachi Research Center, Ltd.

Claims (3)

[Claims] 1. In a device for simulating a semiconductor process, a high-speed simple simulator that can be repeatedly executed a plurality of times to obtain an appropriate input process, and an analysis with higher accuracy than the input process obtained by the simple simulator. Equipped with a high-precision simulator for obtaining results,
A process simulation apparatus comprising a controller for judging that an input process is appropriate based on an analysis result obtained by the simple simulator and switching the processing to the high precision simulator. 2. The process simulation apparatus according to claim 1, wherein the simple simulator is repeatedly executed a plurality of times while changing an input process data until an appropriate input process is obtained. 3. The process simulation apparatus according to claim 1, further comprising means for externally inputting a response to the analysis result obtained by the simple simulator.