阅读说明：本技术 半导体测试图案及其测试方法 (Semiconductor test pattern and test method thereof ) 是由 袁林山 杨光 欧阳锦坚 吕嘉伟 黄清俊 谈文毅 于 2021-03-03 设计创作，主要内容包括：本发明公开一种半导体测试图案及其测试方法,其中该半导体测试图案包含一高密度元件区,以及多个电阻对,环绕于该高密度元件区的周围,其中每一个电阻对包含有两个相互对称的电阻图案。(The invention discloses a semiconductor test pattern and a test method thereof, wherein the semiconductor test pattern comprises a high-density element area and a plurality of resistor pairs surrounding the periphery of the high-density element area, wherein each resistor pair comprises two mutually symmetrical resistor patterns.)

1. A semiconductor test pattern, comprising:

a high-density device region; and

and a plurality of resistor pairs surrounding the high-density device region, wherein each resistor pair comprises two mutually symmetrical resistor patterns.

2. The semiconductor test pattern according to claim 1, wherein each of the resistor patterns comprises a plurality of strip-shaped resistor patterns arranged in parallel with each other, and a plurality of conductive lines connecting the strip-shaped resistor patterns in series with each other.

3. The semiconductor test pattern of claim 2, wherein the plurality of resistor pairs comprises a plurality of resistor pairs arranged along a first direction, and the remaining portion of the test pattern comprises a plurality of resistor pairs arranged along a second direction.

4. The semiconductor test pattern of claim 3, wherein the first direction and the second direction are perpendicular to each other.

5. The semiconductor test pattern as claimed in claim 3, wherein the plurality of resistor pairs arranged along the first direction include a plurality of bar-shaped resistor patterns arranged along the first direction, and the plurality of resistor pairs arranged along the second direction include a plurality of bar-shaped resistor patterns arranged along the second direction.

6. The semiconductor test pattern of claim 1, wherein a shortest distance between any of the plurality of resistor pairs and the high-density device region is between 1.5 microns and 50 microns.

7. A method for testing a semiconductor test pattern, comprising:

providing a semiconductor test pattern, the semiconductor test pattern comprising:

a high-density device region;

a plurality of resistor pairs surrounding the high-density device region, wherein each resistor pair comprises two symmetrical resistor patterns; and

performing a laser heating step on the semiconductor test pattern; and

the resistance change of each resistance pair of the semiconductor test pattern is tested.

8. The testing method of claim 7, wherein each of the resistor patterns comprises a plurality of resistor bar patterns arranged in parallel, and a plurality of conductive lines connecting the resistor bar patterns in series.

9. The method of claim 8, wherein the plurality of resistor pairs comprises a plurality of resistor pairs arranged along a first direction, and the remaining portion of the test pattern comprises a plurality of resistor pairs arranged along a second direction.

10. The testing method of claim 9, wherein the first direction and the second direction are perpendicular to each other.

11. The testing method of claim 9, wherein the plurality of resistor pairs arranged along the first direction include a plurality of bar-shaped resistor patterns arranged along the first direction, and the plurality of resistor pairs arranged along the second direction include a plurality of bar-shaped resistor patterns arranged along the second direction.

12. The method of claim 7, wherein the step of laser heating the semiconductor test pattern comprises:

providing a plurality of substrates, wherein each substrate comprises a semiconductor test pattern;

performing a laser heating step on the semiconductor test pattern of one of the substrates from an angle;

from another angle, performing a laser heating step on the semiconductor test pattern of another substrate; and

the most suitable angle is found.

13. The method according to claim 12, wherein the laser heating step comprises laser heating the semiconductor test pattern from the most suitable angle in a scanning manner.

14. The method of claim 7, wherein testing the semiconductor test pattern for resistance variations comprises:

after the laser heating step is performed, a resistance difference value between the two resistance patterns of each resistance pair is measured.

15. The testing method of claim 7, wherein a shortest distance between any of the plurality of resistor pairs and the high-density device region is between 1.5 microns and 50 microns.

Technical Field

The invention relates to the field of semiconductor manufacturing processes, in particular to a semiconductor test pattern comprising a plurality of resistor pairs (pair resistors).

Background

In the field of semiconductor fabrication process, a resistor (resistor) is a common electronic component. In some implementations, the resistors are fabricated in pairs for use in electronic products, such as earphones, that are also paired.

However, even if the pair of resistors have the same or symmetrical patterns, some of the steps in the semiconductor manufacturing process may affect the resistance of the resistors, cause the resistances of the two sides of the pair of resistors to be unequal, and affect the quality of the electronic product to be formed later (e.g., cause the left and right sides of the earphone to have different sound sizes).

Disclosure of Invention

Therefore, there is a need to provide improved methods to solve the above problems.

The invention provides a semiconductor test pattern, which comprises a high-density element area and a plurality of resistor pairs surrounding the periphery of the high-density element area, wherein each resistor pair comprises two mutually symmetrical resistor patterns.

The present invention also provides a method for testing a semiconductor test pattern, comprising providing a semiconductor test pattern comprising a high density device region, a plurality of resistor pairs surrounding the high density device region, wherein each resistor pair comprises two symmetrical resistor patterns, performing a laser heating step on the semiconductor test pattern, and testing the resistance change of the semiconductor test pattern.

The present invention provides a semiconductor test pattern characterized in that the applicant has found that the laser heating step has a great influence on the resistance of a resistive element, and therefore, in order to find a problem in time at the front end of the manufacturing process, the applicant has provided a test pattern in which a plurality of resistor pairs (pair resistors) are surrounded around a high-density element region. This test pattern can then be used to perform a laser heating step from different angles and to perform hot spot diffusion tests on the resistance effect of the resistor pairs. The semiconductor test pattern provided by the invention can be suitable for testing laser heating steps in different directions, the most suitable manufacturing process parameters can be found out through the testing steps, the problem that the resistance is not right can be found out at the front end of the manufacturing process, the problem can be corrected in time, and the yield and the efficiency of the manufacturing process can be improved.

Drawings

FIG. 1 is a schematic top view of a semiconductor test pattern according to an embodiment of the present invention;

FIG. 2 is an enlarged schematic view of a portion of a resistor pair;

FIG. 3 is a schematic top view of the semiconductor test pattern of FIG. 1 tested for a laser heating step from a different orientation;

FIG. 4 is a cross-sectional view of one of the lasers.

Description of the main elements

1: semiconductor test pattern

10 base

20 high density device region

30 pair of resistors

30A resistance pattern

30B resistance pattern

40 bar resistor pattern

50: conducting wire

A is the included angle

L1, L2, L3, L4, L5, L6, L7, L8 laser

Detailed Description

In order to make the present invention more comprehensible to those skilled in the art, preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings.

For convenience of explanation, the drawings are only schematic to facilitate understanding of the present invention, and the detailed proportions thereof may be adjusted according to design requirements. The relative positions of elements in the figures described herein are understood by those skilled in the art to refer to relative positions of objects and thus all parts may be turned over to present the same elements, all falling within the scope of the present disclosure and all described herein.

It is an object of the present invention to design a semiconductor test pattern for observing the effect of the laser heating step on the resistance pair (pair resistor).

To achieve the above objective, referring to fig. 1, fig. 1 is a schematic top view of a semiconductor test pattern according to an embodiment of the invention. First, a high-density device region 20 is formed on a substrate 10, and then a plurality of resistor pairs 30 are formed around the high-density device region 20, wherein each resistor pair 30 is composed of two resistor patterns 30A and 30B in pairs. That is, each two paired resistance patterns 30A, 30B collectively constitute one resistance pair 30. The above-described elements on the substrate 10 constitute a semiconductor test pattern 1.

Fig. 2 is an enlarged schematic diagram of a part of the resistor pairs. As shown in fig. 2, the resistor pattern 30A or 30B of each resistor pair 30 includes a plurality of resistor bar patterns 40 arranged in parallel, and a plurality of wires 50 connecting the resistor bar patterns 40 in series. The resistor pairs 30 may include longitudinally arranged resistor pairs 30 (or arranged along the Y direction, such as the left resistor pairs 30 in fig. 2) and transversely arranged resistor pairs 30 (or arranged along the X direction, such as the right resistor pairs 30 in fig. 2), according to the arrangement direction of the resistor bar patterns 40. It should be noted that the present invention does not limit the resistor pairs to be arranged only in the transverse direction or the longitudinal direction, and the resistor pairs may be arranged in other directions, and also fall within the scope of the present invention. In addition, it is preferable that the two resistor patterns 30A and 30B included in any resistor pair 30 are arranged in the same direction, for example, both are arranged in the longitudinal direction, or both are arranged in the transverse direction.

Referring again to fig. 1, in the present embodiment, a plurality of resistor pairs 30 are arranged around the high-density device region 20, and preferably, adjacent resistor pairs 30 have different arrangement directions, for example, one longitudinally arranged resistor pair 30 is located between two transversely arranged resistor pairs 30, and similarly, one transversely arranged resistor pair 30 is located between two longitudinally arranged resistor pairs 30. In addition, in the present embodiment, the shortest distance between the high-density device region 20 and any one of the resistor pairs 30 is preferably between 1.5 microns and 50 microns.

The high-density device region 20 includes, for example, a polysilicon pattern or a doped region, wherein the density of the device is preferably higher than 60%, and the size of the high-density device region 20 is preferably between 100 to 10000 μm, but the invention is not limited thereto. Generally, the high-density device region 20 is a circuit pattern region disposed beside a resistor pair in an actual product, and may include circuit patterns such as transistor switches, driving devices, and the like. These elements are well known in the art and will not be described in further detail herein.

Applicants have discovered that there are a number of factors that affect the resistance of the resistor pairs during the semiconductor fabrication process, such as the laser heating step (including laser orientation, temperature, hot spot diffusion), the density of the regions (e.g., shallow trench isolation or device regions) adjacent to the resistor pairs, the orientation (lateral or longitudinal) of the resistor pairs themselves, and the like, which may affect the resistance of the resistor pairs and cause the resistance of the resistor pairs to be different (or referred to as mismatch) on both sides. According to the experimental results of the applicant, the direction of the laser heating step and the arrangement direction of the resistor pairs have great influence on the resistance values of the resistor pairs. Specifically, the laser affects the resistance of the resistor pair, and the higher the laser heating temperature, the lower the resistance of the resistor. In addition, the direction of the laser and the arrangement direction of the resistor pairs also affect the resistance of the resistor pairs, for example, if the irradiation direction of the laser is perpendicular to the arrangement direction of the resistor pairs, the resistor pairs easily absorb more heat energy, which results in more obvious decrease of the resistance. Therefore, the semiconductor test pattern provided in FIG. 1 of the present invention can be used to test the effect of the laser heating step and the direction of the resistor pair on the resistance of the resistor pair. The test method is described in the following paragraphs:

FIG. 3 is a schematic top view showing a laser heating step test performed on the semiconductor test pattern shown in FIG. 1 from different directions, and FIG. 4 is a schematic cross-sectional view showing one of the lasers. As shown in fig. 3, the semiconductor test pattern 1 shown in fig. 1 may be respectively subjected to laser heating steps from different directions, and the lasers in different directions in fig. 3 are denoted by different reference numerals, for example, as laser L1, laser L2, laser L3, laser L4, laser L5, laser L6, laser L7, and laser L8. It should be noted that each of the lasers L1-L8 represents one of the laser heating test steps, and the laser heating steps are performed in different directions on different substrates. In other words, a plurality of substrates each having the same semiconductor test pattern 1 formed thereon may be prepared in advance, and then the laser heating steps may be performed in different directions for the semiconductor test patterns 1 on different substrates.

Referring to fig. 4, in the present embodiment, the direction of the laser beam toward the semiconductor test pattern 1 is adjusted (for example, the laser beams L1-L8, fig. 4 uses L1 as an example) to fix the angle between the laser beam and the horizontal plane of the substrate (for example, in fig. 4, the angle a between the laser beam and the horizontal plane of the substrate is fixed to 75 degrees, but not limited thereto). Through multiple laser heating steps and after each laser heating step, the resistance pair on the semiconductor test pattern 1 is measured, specifically, for example, the difference between the resistance values of the two resistance patterns 30A and 30B included in the resistance pair 30 is measured, so as to find out the laser heating direction having the smallest influence on the resistance value, and at the same time, find out the more suitable arrangement direction (for example, the transverse direction or the longitudinal direction) of the resistance pair. Preferably, after the laser heating step is performed, the difference between the resistance values of the two sides of the resistor pair is within 0.5%, which is better in accordance with the use specification.

In addition, although the angle a between the laser and the substrate horizontal plane is fixed (for example, 75 degrees) in this embodiment, in other embodiments of the present invention, the angle between the laser and the substrate horizontal plane may be adjusted by setting it as a variable, and this concept also falls within the scope of the present invention.

In the present embodiment, the purpose of arranging the plurality of resistor pairs 30 around the high-density device region 20 is to design a semiconductor test pattern that can be applied to a plurality of laser test directions. In other words, according to the semiconductor test pattern shown in fig. 1, the resistor pairs 30 and the high-density device regions 20 can be irradiated with laser experiments from different directions without changing the semiconductor test pattern according to different laser directions, thereby saving test steps.

In addition, another purpose of arranging the plurality of resistor pairs 30 around the high-density element region 20 in this embodiment is to observe the influence of hot spot (hot spot) diffusion on the resistance value from various directions. The hot spot diffusion is a phenomenon that when the laser is irradiated to the boundary of the high-density device region 20, since the region belongs to a region where the device density is largely changed, the rate of thermal energy conduction to the surrounding region and the cooling rate are different, for example, the rate of thermal energy cooling is slow toward a region where the devices are densely arranged, and the rate of thermal energy cooling is fast toward an open region (a region where the device density is low), which is also referred to as hot spot diffusion. In the present embodiment, since the pair of resistors 30 are arranged around the high-density element region 20, the laser light can be irradiated to the boundary of the high-density element region 20 regardless of the laser heating step performed from each angle, whereby the influence of the resistance value of the pair of resistors 30 around the high-density element region 20 under the spread of the hot spot can be observed.

After the laser heating step test is completed, the most suitable manufacturing process parameters can be found, namely the manufacturing process parameters which have the smallest influence on the resistance value difference of the resistor pairs, and part of the resistor pairs can be subjected to fine adjustment (such as fine adjustment patterns) so as to further reduce the resistance value difference of the resistor pairs. This provides better parameters for the subsequent actual manufacturing process steps.

In some embodiments of the present invention, a semiconductor test pattern 1 is provided, which includes a high density device region 20, and a plurality of resistor pairs 30 surrounding the high density device region, wherein each resistor pair includes two symmetrical resistor patterns 30A and 30B.

In some embodiments of the present invention, each of the resistor patterns 30A and 30B includes a plurality of resistor bar patterns 40 arranged in parallel, and a plurality of conductive lines 50 connecting the resistor bar patterns 40 in series.

In some embodiments of the present invention, the plurality of resistor pairs 30 includes a plurality of resistor pairs 30 arranged along a first direction (e.g., the left-side vertically arranged resistor pairs in fig. 2), and the remaining portion of the test pattern includes a plurality of resistor pairs 30 arranged along a second direction (e.g., the right-side horizontally arranged resistor pairs in fig. 2).

In some embodiments of the present invention, the first direction and the second direction are perpendicular to each other (e.g., transverse and longitudinal, or X and Y directions).

In some embodiments of the present invention, the plurality of resistor pairs 30 arranged along the first direction include a plurality of bar-shaped resistor patterns 40 arranged along the first direction, and the plurality of resistor pairs 30 arranged along the second direction include a plurality of bar-shaped resistor patterns 40 arranged along the second direction.

In some embodiments of the present invention, a shortest distance between any of the plurality of resistor pairs 30 and the high-density device region 20 is between 1.5 microns and 50 microns.

In some embodiments of the present invention, a method for testing a semiconductor test pattern is provided, which includes providing a semiconductor test pattern 1, the semiconductor test pattern 1 including a high density device region 20, a plurality of resistor pairs 30 surrounding the high density device region 20, wherein each resistor pair 30 includes two mutually symmetrical resistor patterns 30A and 30B, and performing a laser heating step on the semiconductor test pattern, and testing the resistance variation of each resistor pair of the semiconductor test pattern.

In some embodiments of the present invention, performing a laser heating step on the semiconductor test patterns 1 includes providing a plurality of substrates each including one of the semiconductor test patterns 1, performing a laser heating step on the semiconductor test pattern of one of the substrates from one angle, performing a laser heating step on the semiconductor test pattern of the other substrate from another angle, and finding an optimum angle.

In some embodiments of the present invention, wherein the laser heating step comprises laser heating the semiconductor test pattern from the most suitable angle and in a scanning manner.

In some embodiments of the present invention, wherein testing the semiconductor test patterns for resistance variations comprises measuring a resistance difference between the two resistance patterns of each resistance pair after the laser heating step is performed.

In summary, the present invention provides a semiconductor test pattern, which is characterized in that the applicant finds that the laser heating step has a large influence on the resistance of the resistor element, and therefore, in order to find a problem in time at the front end of the manufacturing process, the applicant provides a test pattern in which a plurality of resistor pairs (pairs) are surrounded around the high-density element region. This test pattern can then be used to perform a laser heating step from different angles and to perform hot spot diffusion tests on the resistance effect of the resistor pairs. The semiconductor test pattern provided by the invention can be suitable for testing laser heating steps in different directions, the most suitable manufacturing process parameters can be found out through the testing steps, the problem that the resistance is not right can be found out at the front end of the manufacturing process, the problem can be corrected in time, and the yield and the efficiency of the manufacturing process can be improved.

The above description is only a preferred embodiment of the present invention, and all equivalent changes and modifications made in the claims of the present invention should be covered by the present invention.