A Method for Measuring Stress Gradients in Different Directions of Thin Films

Abstract

The invention provides a method for measuring stress gradients in different directions of a thin film, comprising the steps of: obtaining the slope equivalent coefficient K of the thin film based on the S11 stress gradient in the first direction through simulation X1 , Slope equivalent coefficient K based on S22 stress gradient X2 ; Obtain the slope equivalent coefficient K of the film in the second direction based on the S11 stress gradient through simulation Y1 , Slope equivalent coefficient K based on S22 stress gradient Y2 ; Obtain the slope K in the first direction of the film through actual testing 1 and the slope K in the second direction 2 ; According to the K X1 、K X2 、K Y1 、K Y2 , and K 1 、K 2 Calculate the stress gradients in the first direction and the second direction of the film. The invention has higher measurement accuracy and is simpler.

Description

Technical field

[0001] The invention relates to the field of semiconductor devices, in particular to a method for measuring stress gradients in different directions of a thin film.

Background technique

[0002] In the field of MEMS, stress gradients generally exist in the device structure, causing structural deformation and affecting device performance.

[0003] At present, the commonly used method for measuring the stress gradient is: setting up a series of single-end fixed cantilever beam structures with different lengths, and then measuring the warpage of the ends of the beams with different lengths, and then bringing it into the formula to calculate the stress gradient. This method usually assumes that the stress gradients of S11 (positive stress in the X-axis direction) or S22 (positive stress in the Y-axis direction) are consistent.

[0004] However, in actual situations, the stress magnitudes of S11 or S22 of the film are often inconsistent, so that the above cal...

Examples

Embodiment 1

[0047] Reference attached figure 1 As shown, the present embodiment discloses a method for measuring stress gradients in different directions of a thin film, comprising steps:

[0048] T1. Obtain the slope equivalent coefficient K of the film in the first direction based on the S11 stress gradient through simulation X1 , Slope equivalent coefficient K based on S22 stress gradient X2 ;

[0049] T2. Obtain the slope equivalent coefficient K of the film in the second direction based on the S11 stress gradient through simulation Y1 , Slope equivalent coefficient K based on S22 stress gradient Y2 ;

[0050] T3. Obtain the slope K in the first direction of the film through actual testing 1 and the slope K in the second direction 2 ;

[0051] T4, according to K X1 、K X2 、K Y1 、K Y2 , and K 1 、K 2 Calculate the stress gradient in the first direction and the second direction of the film.

[0052] It should be noted that, in this embodiment, the above steps T1, T2, and T3 ...

Technical field

[0001] The invention relates to the field of semiconductor devices, in particular to a method for measuring stress gradients in different directions of a thin film.

Background technique

[0002] In the field of MEMS, stress gradients generally exist in the device structure, causing structural deformation and affecting device performance.

[0003] At present, the commonly used method for measuring the stress gradient is: setting up a series of single-end fixed cantilever beam structures with different lengths, and then measuring the warpage of the ends of the beams with different lengths, and then bringing it into the formula to calculate the stress gradient. This method usually assumes that the stress gradients of S11 (positive stress in the X-axis direction) or S22 (positive stress in the Y-axis direction) are consistent.

[0004] However, in actual situations, the stress magnitudes of S11 or S22 of the film are often inconsistent, so that the above cal...

Examples

Embodiment 1

[0047] Reference attached figure 1 As shown, the present embodiment discloses a method for measuring stress gradients in different directions of a thin film, comprising steps:

[0048] T1. Obtain the slope equivalent coefficient K of the film in the first direction based on the S11 stress gradient through simulation X1 , Slope equivalent coefficient K based on S22 stress gradient X2 ;

[0049] T2. Obtain the slope equivalent coefficient K of the film in the second direction based on the S11 stress gradient through simulation Y1 , Slope equivalent coefficient K based on S22 stress gradient Y2 ;

[0050] T3. Obtain the slope K in the first direction of the film through actual testing 1 and the slope K in the second direction 2 ;

[0051] T4, according to K X1 、K X2 、K Y1 、K Y2 , and K 1 、K 2 Calculate the stress gradient in the first direction and the second direction of the film.

[0052] It should be noted that, in this embodiment, the above steps T1, T2, and T3 ...

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