阅读说明：本技术 应力解耦和粒子过滤器集成 (Stress decoupling and particle filter integration ) 是由 F·布兰德尔 C·盖斯勒 R·格林贝格尔 C·韦希特尔 B·温克勒 于 2020-03-26 设计创作，主要内容包括：本公开涉及应力解耦和粒子过滤器集成。提供一种半导体器件及其制造方法。半导体器件包括：衬底,具有第一表面和与第一表面相对布置的第二表面；应力敏感传感器,设置在衬底的第一表面处,其中应力敏感传感器对机械应力敏感；应力解耦沟槽,具有从第一表面延伸到衬底中的竖直延伸,其中应力解耦沟槽朝向第二表面竖直地部分延伸至衬底中,但未完全延伸到第二表面；以及多个粒子过滤器沟槽,从第二表面竖直地延伸至衬底中,其中多个粒子过滤器沟槽中的每个粒子过滤器沟槽具有与应力解耦沟槽的竖直延伸正交延伸的纵向延伸。(The present disclosure relates to stress decoupling and particle filter integration. A semiconductor device and a method of manufacturing the same are provided. The semiconductor device includes: a substrate having a first surface and a second surface disposed opposite the first surface; a stress sensitive sensor disposed at the first surface of the substrate, wherein the stress sensitive sensor is sensitive to mechanical stress; a stress decoupling trench having a vertical extension extending from the first surface into the substrate, wherein the stress decoupling trench extends vertically partially into the substrate towards the second surface, but not fully into the second surface; and a plurality of particle filter trenches extending vertically into the substrate from the second surface, wherein each particle filter trench of the plurality of particle filter trenches has a longitudinal extension extending orthogonally to the vertical extension of the stress decoupling trench.)

1. A semiconductor device, comprising:

a substrate having a first surface and a second surface disposed opposite the first surface;

a first stress-sensitive sensor disposed at the first surface of the substrate, wherein the first stress-sensitive sensor is sensitive to mechanical stress;

a first stress decoupling trench having a vertical extension extending from the first surface into the substrate, wherein the first stress decoupling trench extends vertically partially into the substrate toward the second surface, but not fully into the second surface; and

a plurality of particle filter trenches extending vertically into the substrate from the second surface, wherein each particle filter trench of the plurality of particle filter trenches has a longitudinal extension extending orthogonally to the vertical extension of the first stress decoupling trench, and

wherein each particle filter trench of the plurality of particle filter trenches is separated from an adjacent particle filter trench of the plurality of particle filter trenches by a backside portion of the substrate extending from the second surface to a bottom of the first stress decoupling trench.

2. The semiconductor device of claim 1, wherein said each particle filter trench of said plurality of particle filter trenches intersects said first stress decoupling trench in a crisscrossing pattern.

3. The semiconductor device of claim 1, wherein the first stress decoupling trench comprises the vertical extension along a first axis, a longitudinal extension along a second axis orthogonal to the first axis, and a lateral extension along a third axis orthogonal to the first and second axes, and the longitudinal extensions of the plurality of particle filter trenches are arranged at an angle parallel to or between the second and third axes.

4. The semiconductor device of claim 3, wherein the plurality of particle filter trenches are separated from each other along the second axis.

5. The semiconductor device of claim 1, wherein the substrate is of one-piece unitary construction.

6. The semiconductor device of claim 1, wherein each particle filter trench of the plurality of particle filter trenches intersects the bottom of the first stress decoupling trench such that the plurality of particle filter trenches combines with the first stress decoupling trench to form a plurality of openings extending from the first surface to the second surface.

7. The semiconductor device of claim 6, wherein said each particle filter trench of said plurality of particle filter trenches forms a cross pattern or an X pattern with said first stress decoupling trench.

8. The semiconductor device of claim 1, further comprising:

a second stress decoupling trench adjacent to the first stress decoupling trench, the second stress decoupling trench having a vertical extension extending from the first surface into the substrate, wherein the second stress decoupling trench extends vertically partially into the substrate toward the second surface, but not fully into the second surface,

wherein the longitudinal extension of each particle filter trench of the plurality of particle filter trenches laterally spans the first and second stress decoupling trenches.

9. The semiconductor device of claim 8, wherein each particle filter trench of the plurality of particle filter trenches intersects the first stress decoupling trench in a crossing pattern and intersects the second stress decoupling trench in a crossing pattern.

10. The semiconductor device of claim 1, wherein:

the first stress decoupling trench surrounds a periphery of a stress sensitive region of the substrate, the first stress sensitive sensor is disposed in the stress sensitive region,

the plurality of particle filter trenches are arranged at different sides of the periphery of the stress sensitive region along the first stress decoupling trench, and

each particle filter trench of the plurality of particle filter trenches intersects the first stress decoupling trench in a crisscross pattern.

11. The semiconductor device of claim 1, further comprising:

a first stress sensitive region of the substrate, the first stress sensitive sensor being disposed in the first stress sensitive region;

a second stress-sensitive sensor disposed at the first surface of the substrate in a second stress-sensitive region of the substrate, wherein the second stress-sensitive sensor is sensitive to mechanical stress; and

a plurality of stress decoupling grooves including the first stress decoupling groove disposed between the first stress sensitive region and the second stress sensitive region,

wherein the longitudinal extension of each particle filter trench of the plurality of particle filter trenches laterally spans the first and second stress decoupling trenches such that the plurality of particle filter trenches intersect a bottom of each of the first and second stress decoupling trenches.

12. The semiconductor device of claim 1, wherein:

the longitudinal extension of each particle filter channel of the plurality of particle filter channels extends from the first stress sensitive region to the second stress sensitive region.

13. A method of manufacturing a semiconductor device, the method comprising:

performing front end fabrication of a semiconductor substrate having a first surface and a second surface disposed opposite the first surface, the front end fabrication including integrating a first stress-sensitive sensor disposed at the first surface of the substrate, and forming the first stress decoupling trench in the substrate, wherein the first stress decoupling trench has a vertical extension extending from the first surface into the substrate, wherein the first stress decoupling trench extends vertically partially into the substrate toward the second surface, but not fully into the second surface; and

forming a plurality of particle filter trenches at the second surface of the substrate, wherein the plurality of particle filter trenches extend vertically into the substrate from the second surface, wherein each particle filter trench of the plurality of particle filter trenches has a longitudinal extension that extends orthogonally to the vertical extension of the first stress decoupling trench, an

Wherein each particle filter trench of the plurality of particle filter trenches is separated from an adjacent particle filter trench of the plurality of particle filter trenches by a backside portion of the substrate extending from the second surface to a bottom of the first stress decoupling trench.

14. The method of claim 13, further comprising:

attaching a cover to the first surface, wherein the cover encloses the first stress-sensitive sensor and the first stress-decoupling groove.

15. The method of claim 14, wherein the front end fabrication includes forming contact pads on the first surface, and the cap, the first stress sensitive sensor, and the first stress decoupling groove are disposed between the contact pads.

16. The method of claim 15, wherein the cover is an interposer comprising conductive vias aligned with the contact pads.

17. The method of claim 13, wherein the first stress decoupling grooves comprise the vertical extension along a first axis, a longitudinal extension along a second axis orthogonal to the first axis, and a lateral extension along a third axis orthogonal to the first and second axes, and the longitudinal extensions of the plurality of particle filter grooves are arranged at an angle parallel to or between the second and third axes.

18. The method of claim 17, wherein the plurality of particle filter channels are separated from one another along the second axis.

19. The method of claim 13, wherein each particle filter trench of the plurality of particle filter trenches forms a cross pattern or an X pattern with the first stress decoupling trench.

20. The method of claim 13, wherein each particle filter trench of the plurality of particle filter trenches intersects the bottom of the first stress decoupling trench such that the plurality of particle filter trenches combines with the first stress decoupling trench to form a plurality of openings extending from the first surface to the second surface.

Technical Field

The present disclosure relates generally to semiconductor devices and methods of fabricating the same, and more particularly to stress sensitive sensors having stress relief mechanisms.

Background

Microelectromechanical Systems (MEMS) are microscopic devices, particularly those having moving parts. MEMS have become practical once they can be fabricated using improved semiconductor device fabrication techniques that are commonly used to fabricate electronic products. Thus, MEMS can be built into a substrate as a component of an integrated circuit, the substrate is cut into semiconductor chips, and then mounted in a package.

Mechanical stresses, including stresses generated by the chip package, as well as external mechanical influences introduced into the package, may be inadvertently transmitted through the package to the integrated MEMS element, such as the sensor, and more particularly, to the pressure sensor. This transferred mechanical stress may affect the operation of the MEMS element or cause a shift (e.g., offset) in the sensor signal, which may result in erroneous measurements.

For example, semiconductor pressure sensors have pressure sensitive elements arranged to measure absolute pressure or relative pressure (e.g., the difference between two pressures). A problem with many pressure sensors is that: the sensor measures (or outputs, or gives) a signal even if there is no pressure (or pressure difference) to be measured. The offset may be the result of mechanical stress and/or deformation of the sensor housing (e.g., package). The housing stress/deformation also typically causes stress components on the sensor surface where the sensitive element (e.g., piezoresistor) is located, and thus offset errors, linearity errors, and even hysteresis errors of the output signal.

Accordingly, improved devices capable of decoupling mechanical stress from integrated MEMS elements may be desired.

Disclosure of Invention

Drawings

Embodiments are described herein with reference to the accompanying drawings.

FIG. 1A illustrates a vertical cross-sectional view of a chip taken along line A-A in FIGS. 1B and 1C in accordance with one or more embodiments;

FIGS. 1B and 1C illustrate top and bottom views, respectively, of the chip shown in FIG. 1A in accordance with one or more embodiments;

FIG. 1D illustrates a vertical cross-sectional view of a chip taken along line B-B in FIGS. 1B and 1C in accordance with one or more embodiments;

FIG. 2 illustrates a cross-sectional view of a chip in accordance with one or more embodiments;

FIG. 3A shows a top view of a chip in accordance with one or more embodiments;

FIG. 3B shows a cross-sectional view of the chip taken along line C-C in FIG. 3A;

4A-4D show cross-sectional views illustrating a manufacturing process of an integrated stress sensitive sensor according to one or more embodiments;

FIGS. 5A-5G show cross-sectional views illustrating a fabrication process of an integrated stress sensitive sensor including Wafer Level Ball (WLB) grid array integration in accordance with one or more embodiments; and

fig. 6A and 6B show cross-sectional views illustrating an alternative fabrication process including integrated stress sensitive sensors integrated with WLB grid array integration in accordance with one or more embodiments.

Embodiments provide a semiconductor device and a method of manufacturing the same, and more particularly, a stress sensitive sensor having a stress relief mechanism.

One or more embodiments provide a semiconductor device including: a substrate having a first surface and a second surface disposed opposite the first surface; a first stress sensitive sensor disposed at the first surface of the substrate, wherein the first stress sensitive sensor is sensitive to mechanical stress; a first stress decoupling trench having a vertical extension into the substrate from the first surface, wherein the first stress decoupling trench extends vertically partially into the substrate towards the second surface, but not fully into the second surface; and a plurality of particle filter trenches extending vertically into the substrate from the second surface, wherein each particle filter trench of the plurality of particle filter trenches has a longitudinal extension extending orthogonally to the vertical extension of the first stress decoupling trench, and wherein each particle filter trench of the plurality of particle filter trenches is separated from an adjacent particle filter trench of the plurality of particle filter trenches by a backside portion of the substrate extending from the second surface to a bottom of the first stress decoupling trench.

One or more further embodiments provide a method of manufacturing a semiconductor device. The method comprises the following steps: performing front end fabrication of a semiconductor substrate, the semiconductor substrate having a first surface and a second surface disposed opposite the first surface, the front end fabrication including a first stress-sensitive sensor integrally disposed at the first surface of the substrate, and forming a stress decoupling trench in the first substrate, wherein the first stress decoupling trench has a vertical extension extending from the first surface into the substrate, wherein the first stress decoupling trench extends vertically partially into the substrate toward the second surface, but not fully into the second surface; and forming a plurality of particle filter trenches at the second surface of the substrate, wherein the plurality of particle filter trenches extend vertically into the substrate from the second surface, wherein each particle filter trench of the plurality of particle filter trenches has a longitudinal extension that extends orthogonally to the vertical extension of the first stress decoupling trench, and wherein each particle filter trench of the plurality of particle filter trenches is separated from an adjacent particle filter trench of the plurality of particle filter trenches by a backside portion of the substrate that extends from the second surface to a bottom of the first stress decoupling trench.