阅读说明：本技术 集成电路元件及其制作方法 (Integrated circuit element and manufacturing method thereof ) 是由 马瑞吉 杨国裕 林家辉 张竹君 于 2020-05-25 设计创作，主要内容包括：本发明公开一种集成电路元件及其制作方法,其中该集成电路元件包含：一基底；一集成电路区域,位于所述基底上,所述集成电路区域包含一介电堆叠；一密封环,设于所述介电堆叠中,并环绕于所述集成电路区域周围；一沟槽,环绕所述密封环,并显露出所述介电堆叠的一侧壁；一湿气阻隔层,连续的覆盖所述集成电路区域,并延伸至所述介电堆叠的所述侧壁,从而密封所述介电堆叠中的两个相邻介电膜之间的交界；以及一钝化层,位于所述湿气阻隔层上。(The invention discloses an integrated circuit element and a manufacturing method thereof, wherein the integrated circuit element comprises: a substrate; an integrated circuit region on the substrate, the integrated circuit region comprising a dielectric stack; a seal ring disposed in the dielectric stack and surrounding the integrated circuit region; a trench surrounding the seal ring and exposing a sidewall of the dielectric stack; a moisture barrier layer continuously covering the integrated circuit region and extending to the sidewall of the dielectric stack, thereby sealing an interface between two adjacent dielectric films in the dielectric stack; and a passivation layer on the moisture barrier layer.)

1. An integrated circuit device, comprising:

a substrate;

an integrated circuit region on the substrate, the integrated circuit region comprising a dielectric stack;

a seal ring disposed in the dielectric stack and surrounding the integrated circuit region;

a trench surrounding the seal ring and exposing a sidewall of the dielectric stack;

a moisture barrier layer continuously covering the integrated circuit region and extending to the sidewall of the dielectric stack, thereby sealing an interface between two adjacent dielectric films in the dielectric stack; and

a passivation layer on the moisture barrier layer.

2. The integrated circuit element of claim 1, wherein the integrated circuit region comprises radio frequency circuitry.

3. The integrated circuit device of claim 1, wherein the substrate is a silicon-on-insulator substrate comprising a lower substrate, a buried oxide layer, and a device layer on the buried oxide layer.

4. The integrated circuit element of claim 3, wherein the element layer comprises a silicon layer.

5. The integrated circuit device of claim 3, wherein the seal ring is electrically coupled to the lower substrate via a through contact penetrating the device layer and the buried oxide layer.

6. The integrated circuit component of claim 1 wherein the two adjacent dielectric films are two adjacent low dielectric constant dielectric films.

7. The integrated circuit element of claim 1, wherein the seal ring is a discontinuous seal ring.

8. The integrated circuit device of claim 7, wherein the seal ring is comprised of interconnected metal lines and vias.

9. The integrated circuit device of claim 8, wherein the metal line comprises an uppermost copper metal line, and the moisture barrier layer directly contacts the uppermost copper metal line.

10. The integrated circuit device of claim 9, wherein said uppermost copper metal line is an uppermost damascene copper metal line and said moisture barrier layer simultaneously serves as a capping layer covering a top surface of said uppermost damascene copper metal line.

11. The integrated circuit device of claim 10, further comprising:

an uppermost dielectric film covering the dielectric stack;

an uppermost via hole penetrating the uppermost dielectric film and the moisture barrier layer to electrically connect with the uppermost copper wire; and

and the aluminum pad is arranged on the interlayer through hole on the uppermost layer and is electrically connected with the interlayer through hole on the uppermost layer.

12. The integrated circuit element of claim 11, wherein the passivation layer covers a periphery of the aluminum pad and a top surface of the uppermost dielectric film.

13. The integrated circuit element of claim 12 wherein the uppermost dielectric film comprises silicon oxide.

14. The integrated circuit element of claim 12, wherein the passivation layer comprises polyimide, silicon nitride, or silicon oxide.

15. The integrated circuit device of claim 1, wherein the moisture barrier layer comprises silicon nitride, silicon oxynitride, or silicon carbonitride.

16. A method of forming an integrated circuit device, comprising:

providing a substrate;

forming an integrated circuit region on the substrate, the integrated circuit region comprising a dielectric stack;

forming a seal ring in the dielectric stack, the seal ring surrounding the integrated circuit region;

forming a trench surrounding the seal ring, the trench exposing a sidewall of the dielectric stack;

forming a moisture barrier layer continuously covering the integrated circuit region and extending to the sidewall of the dielectric stack, thereby sealing an interface between two adjacent dielectric films in the dielectric stack; and

a passivation layer is formed on the moisture barrier layer.

17. The method of claim 16, wherein the integrated circuit region includes radio frequency circuitry.

18. The method of claim 16, wherein the substrate is a silicon-on-insulator substrate comprising a lower substrate, a buried oxide layer, and a device layer on the buried oxide layer.

19. The method of claim 18, wherein the element layer comprises a silicon layer.

20. The method of claim 18, wherein the seal ring is electrically coupled to the lower substrate via a through contact that penetrates the element layer and the buried oxide layer.

21. The method of claim 16, wherein the two adjacent dielectric films are two adjacent low dielectric constant dielectric films.

22. The method of claim 16, wherein the seal ring is a discontinuous seal ring.

23. The method of claim 22, wherein the seal ring is comprised of interconnected metal lines and vias.

24. The method of claim 23, wherein the metal line comprises an uppermost copper metal line.

25. The method of claim 24, wherein said topmost copper metal line is a topmost damascene copper metal line.

26. The method of claim 25, further comprising:

forming an uppermost dielectric film overlying the dielectric stack;

forming an uppermost via hole penetrating the uppermost dielectric film and the moisture barrier layer to electrically connect with the uppermost copper wire; and

forming an aluminum pad disposed on the uppermost interlayer via and electrically connected to the uppermost interlayer via.

27. The method of claim 26, wherein the passivation layer covers a peripheral edge of the aluminum pad and a top surface of the uppermost dielectric film.

28. The method of claim 27, wherein the uppermost dielectric film comprises silicon oxide.

29. The method of claim 27, wherein the passivation layer comprises polyimide, silicon nitride, or silicon oxide.

30. The method of claim 16, wherein the moisture barrier layer comprises silicon nitride, silicon oxynitride, or silicon carbonitride.

Technical Field

The present invention relates to the field of semiconductor technology, and more particularly, to an improved integrated circuit device and a method for fabricating the same.

Background

The formation of the seal ring is an important step in the back-end fabrication process of the semiconductor. The seal ring is a stress protection structure around the integrated circuit, and can protect the internal circuit in the semiconductor chip from being damaged due to wafer cutting.

Another function of the sealing ring is to protect the integrated circuit inside the sealing ring from degradation caused by moisture. Since the dielectric layers of integrated circuits are typically formed of porous low dielectric constant (low-k) dielectric materials, moisture can easily penetrate through the low-k dielectric layers to reach the integrated circuits.

Typically, the seal rings are continuous structures around the periphery of the chip, but the direct electrical path around the chip formed by the continuous seal rings can transmit noise to sensitive analog and RF circuit modules. One conventional solution to prevent noise transmission is to employ electrically discontinuous seal rings, thereby inhibiting a significant portion of the noise transmission. However, the discontinuity of the seal ring can result in moisture and contaminants penetrating into the semiconductor chip.

Disclosure of Invention

It is therefore an objective of the claimed invention to provide an improved integrated circuit device and method for fabricating the same, which overcome the above-mentioned shortcomings and drawbacks of the prior art.

In one aspect, the present invention provides an integrated circuit device, comprising: a substrate; an integrated circuit region on the substrate, the integrated circuit region comprising a dielectric stack; a seal ring disposed in the dielectric stack and surrounding the integrated circuit region; a trench surrounding the seal ring and exposing a sidewall of the dielectric stack; a moisture barrier layer continuously covering the integrated circuit region and extending to the sidewall of the dielectric stack, thereby sealing an interface between two adjacent dielectric films in the dielectric stack; and a passivation layer on the moisture barrier layer.

According to an embodiment of the present invention, the integrated circuit region includes a radio frequency circuit.

According to an embodiment of the present invention, the substrate is a silicon-on-insulator substrate, and includes a lower substrate, a buried oxide layer, and an element layer on the buried oxide layer.

According to an embodiment of the present invention, the device layer includes a silicon layer.

According to an embodiment of the present invention, the seal ring is electrically coupled to the lower substrate through a through contact penetrating the device layer and the buried oxide layer.

According to an embodiment of the present invention, the two adjacent dielectric films are two adjacent low-k dielectric films.

According to an embodiment of the present invention, the sealing ring is a discontinuous sealing ring.

According to an embodiment of the present invention, the seal ring is formed by interconnecting metal lines and vias.

According to an embodiment of the present invention, the metal line includes an uppermost copper metal line, and the moisture barrier layer directly contacts the uppermost copper metal line.

According to an embodiment of the present invention, the uppermost copper metal line is an uppermost damascene copper metal line, and the moisture barrier layer simultaneously serves as a capping layer covering a top surface of the uppermost damascene copper metal line.

According to an embodiment of the present invention, the integrated circuit device further comprises: an uppermost dielectric film covering the dielectric stack; an uppermost via hole penetrating through the uppermost dielectric film and the moisture barrier layer to electrically connect with the uppermost copper wire; and an aluminum pad disposed on and electrically connected to the uppermost interlayer via.

According to an embodiment of the present invention, the passivation layer covers a periphery of the aluminum pad and a top surface of the uppermost dielectric film.

According to an embodiment of the present invention, the uppermost dielectric film comprises silicon oxide.

According to an embodiment of the present invention, the passivation layer comprises polyimide, silicon nitride or silicon oxide.

According to an embodiment of the present invention, the moisture barrier layer comprises silicon nitride, silicon oxynitride or silicon carbonitride.

In another aspect, the present invention provides a method of forming an integrated circuit device, including providing a substrate; forming an integrated circuit region on the substrate, the integrated circuit region comprising a dielectric stack; forming a seal ring in the dielectric stack, the seal ring surrounding the integrated circuit region; forming a trench around the seal ring, the trench exposing a sidewall of the dielectric stack; forming a moisture barrier layer continuously covering the integrated circuit region and extending to the sidewall of the dielectric stack, thereby sealing an interface between two adjacent dielectric films in the dielectric stack; and forming a passivation layer on the moisture barrier layer.

According to an embodiment of the present invention, the integrated circuit region includes a radio frequency circuit.

According to an embodiment of the present invention, the substrate is a silicon-on-insulator substrate, and includes a lower substrate, a buried oxide layer, and a device layer on the buried oxide layer.

According to an embodiment of the present invention, the device layer includes a silicon layer.

According to an embodiment of the present invention, the seal ring is electrically coupled to the lower substrate through a through contact penetrating the device layer and the buried oxide layer.

According to an embodiment of the present invention, the two adjacent dielectric films are two adjacent low-k dielectric films.

According to an embodiment of the present invention, the sealing ring is a discontinuous sealing ring.

According to an embodiment of the present invention, the seal ring is formed by interconnecting metal lines and vias.

According to an embodiment of the present invention, the metal line includes an uppermost copper metal line.

According to an embodiment of the present invention, the top copper line is a top damascene copper line.

According to an embodiment of the present invention, the method further comprises: forming an uppermost dielectric film overlying the dielectric stack; forming an uppermost via hole penetrating through the uppermost dielectric film and the moisture barrier layer to electrically connect with the uppermost copper wire; and forming an aluminum pad on the top layer interlayer through hole and electrically connected with the top layer interlayer through hole.

According to an embodiment of the present invention, the passivation layer covers a periphery of the aluminum pad and a top surface of the uppermost dielectric film.

According to an embodiment of the present invention, the uppermost dielectric film comprises silicon oxide.

According to an embodiment of the present invention, the passivation layer comprises polyimide, silicon nitride or silicon oxide.

According to an embodiment of the present invention, the moisture barrier layer comprises silicon nitride, silicon oxynitride or silicon carbonitride.

Drawings

Fig. 1 to 5 are schematic views illustrating a method for forming an integrated circuit device according to an embodiment of the invention, in which fig. 1 is a schematic top view of the integrated circuit device, and fig. 2 to 5 are cross-sectional views taken along a cut line I-I' in fig. 1.

Description of the main elements

1 Integrated Circuit component

10 integrated circuit area

11 radio frequency circuit

20 cutting street area

30 sealing ring

40 dielectric stack

40a side wall

100 substrate

101 lower substrate

102 buried oxide layer

103 element layer

401 dielectric film

402 interface

403 dielectric film

404 moisture barrier layer

405 uppermost dielectric film

410 patterned photoresist layer

AP aluminum pad

M1 layer 1 metal conductor layer

M2 layer 2 metal wire layer (the top copper wire)

Opening of OB

PL passivation layer

R groove

ST trench isolation region

TV through contact

V1 via

Vn top layer interlayer through hole

Detailed Description

In the following, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the embodiments may be practiced. The following examples are described in sufficient detail to enable those skilled in the art to practice them.

Of course, other embodiments may be utilized and structural, logical, and electrical changes may be made without departing from the embodiments described herein. The following detailed description is, therefore, not to be taken in a limiting sense, and the embodiments included therein are defined by the appended claims.

Fig. 1 to 5 are schematic diagrams illustrating a method for forming an integrated circuit device 1 according to an embodiment of the invention, wherein fig. 1 is a top view of the integrated circuit device 1, and fig. 2 to 5 are cross-sectional views taken along a cut line I-I' in fig. 1.

As shown in fig. 1 and fig. 2, a substrate 100 is first provided, for example, the substrate 100 is a silicon-on-insulator (SOI) substrate, and includes a lower substrate 101, a buried oxide layer 102 and a device layer 103 on the buried oxide layer 102. The lower substrate 101 may be a silicon substrate, the buried oxide layer 102 may be a silicon oxide layer, and the device layer 103 includes a silicon layer, such as a monocrystalline silicon layer.

According to an embodiment of the present invention, an integrated circuit region 10 is formed on the substrate 100. According to an embodiment of the present invention, the integrated circuit region 10 includes a radio-frequency (RF) circuit 11. For simplicity of illustration, the circuit elements and metal interconnect structures of integrated circuit region 10 are not shown in fig. 2. Adjacent to the integrated circuit region 10 is a scribe lane (scriber lane) region 20.

According to an embodiment of the present invention, the integrated circuit region 10 includes a dielectric stack 40. In accordance with an embodiment of the present invention, a structurally and electrically discontinuous seal ring 30 has been formed in the dielectric stack 40, the seal ring 30 surrounding the integrated circuit region 10. The seal ring 30 can protect the rf circuit 11 from damage due to wafer dicing. The electrically discontinuous seal ring 30 may inhibit noise transmission. However, the sealing ring 30 is structurally discontinuous, resulting in a reduced ability to block moisture or contaminants from penetrating the rf circuit 11. The present invention can specifically solve this problem.

According to one embodiment of the present invention, as shown in fig. 2, the dielectric stack 40 has at least two adjacent dielectric films 401 and 403, with an interface 402 between the dielectric films 401 and 403. Moisture or stress may intrude into the rf circuit 11 along the interface 402 between the dielectric film 401 and the dielectric film 403, causing corrosion or damage to the circuit structure. According to an embodiment of the present invention, the two adjacent dielectric films 401 and 403 may be two adjacent low dielectric constant (low-k) dielectric films. The "low dielectric constant dielectric film" refers to a dielectric film having a dielectric constant of less than 2.5.

According to an embodiment of the present invention, the seal ring 30 is formed by interconnecting metal lines M and vias V. For simplicity, fig. 2 only illustrates the layer 1 metal wire layer M1, the layer 2 metal wire layer M2, and the via hole V1 between the layer 1 metal wire layer M1 and the layer 2 metal wire layer M2. According to an embodiment of the present invention, the metal line layer M2 is the top copper line, for example, the top damascene copper line. In other words, in this example, the interconnect structure formed by the dual damascene copper process is used for the layer 2 metal line layer M2 and the via hole V1, and there is no copper interconnect above the layer 2 metal line layer M2. According to an embodiment of the present invention, the seal ring 30 is electrically coupled to the lower substrate 101 via a through contact TV penetrating the device layer 103 and the buried oxide layer 102. According to an embodiment of the present invention, the through contact TV penetrates the trench insulation region ST provided in the device layer 103.

As shown in fig. 3, after the cmp process of the layer 2 metal wire layer M2 is completed, a patterned photoresist layer 410 is formed on the layer 2 metal wire layer M2 and the dielectric film 403. According to an embodiment of the invention, the patterned photoresist layer 410 covers the integrated circuit region 10, exposing the scribe line region 20. Next, an anisotropic dry etching process is performed to etch away the dielectric stack 40 not covered by the patterned photoresist layer 410, exposing the device layer 103 in the scribe line region 20, so as to form a trench R in the scribe line region 20.

According to an embodiment of the present invention, the trench R surrounds the seal ring 30, and the trench R exposes a sidewall 40a of the dielectric stack 40 and the interface 402 between the dielectric film 401 and the dielectric film 403 on the sidewall 40 a. After the trench R is completed, the remaining patterned photoresist layer 410 is then removed.

As shown in fig. 4, a moisture barrier layer 404 is formed to continuously cover the integrated circuit region 10 and extend onto the sidewall 40a of the dielectric stack 40, thereby sealing the interface 402 between two adjacent dielectric films 401 and 403 in the dielectric stack 40, so that the moisture barrier layer 404 can effectively block moisture or contaminants from entering the rf circuit 11. According to an embodiment of the present invention, the moisture barrier layer 404 may comprise silicon nitride, silicon oxynitride or silicon carbonitride. In addition, the moisture barrier layer 404 also directly contacts the upper surfaces of the layer 2 metal wiring layer M2 and the dielectric film 403, and may simultaneously serve as an upper cap layer of the layer 2 metal wiring layer M2. According to an embodiment of the present invention, the moisture barrier layer 404 extends into the scribe line region 20 and covers the device layer 103 in addition to covering the sidewall 40a of the dielectric stack 40.

As shown in FIG. 5, an uppermost dielectric film 405 is then formed overlying the moisture barrier layer 404 and the dielectric stack 40. In accordance with an embodiment of the present invention, the uppermost dielectric film 405 comprises silicon oxide. Next, an uppermost via hole Vn is formed in the uppermost dielectric film 405, penetrating through the uppermost dielectric film 405 and the moisture barrier layer 404, to be electrically connected to the 2 nd metal wiring layer M2. Next, an aluminum pad AP is formed on the top dielectric film 405, and is disposed on the top via hole Vn and electrically connected to the top via hole Vn. Next, a passivation layer PL is deposited conformally covering the uppermost dielectric film 405. According to an embodiment of the present invention, the passivation layer PL includes polyimide, silicon nitride or silicon oxide.

According to an embodiment of the present invention, the passivation layer PL covers the periphery of the aluminum pad AP and the top surface of the uppermost dielectric film 405. According to an embodiment of the present invention, an opening OB may be formed in the passivation layer PL by using a photolithography process and an etching process to expose a portion of the upper surface of the aluminum pad AP for subsequent connection with an external circuit.

Structurally, as shown in fig. 5, the integrated circuit device 1 of the present invention includes: a substrate 100; an integrated circuit region 10 on the substrate 100, the integrated circuit region 10 comprising a dielectric stack 40; a seal ring 30 disposed in the dielectric stack 40 and surrounding the integrated circuit region 10; a trench R surrounding the seal ring 30 and exposing a sidewall 40a of the dielectric stack 40; a moisture barrier layer 404 continuously covering the integrated circuit region 10 and extending to the sidewall 40a of the dielectric stack 40, thereby sealing an interface 402 between two adjacent dielectric films 401, 403 in the dielectric stack 40; and a passivation layer PL on the moisture barrier layer 404.

According to an embodiment of the present invention, the integrated circuit region 10 includes a radio frequency circuit 11. According to an embodiment of the present invention, the substrate 100 is a silicon-on-insulator substrate, and includes a lower substrate 101, a buried oxide layer 102, and a device layer 103 on the buried oxide layer 102. According to an embodiment of the present invention, the device layer 103 comprises a silicon layer.

According to an embodiment of the present invention, the seal ring 30 is a discontinuous seal ring according to an embodiment of the present invention, wherein the seal ring 30 is formed by interconnecting metal lines M and vias V. According to an embodiment of the present invention, the metal line M includes an uppermost copper metal line M2, and the moisture barrier layer 404 directly contacts the uppermost copper metal line M2. According to an embodiment of the present invention, the top copper metal line M2 is a top damascene copper line, and the moisture barrier layer 404 also serves as a capping layer covering the top surface of the top damascene copper line. According to an embodiment of the present invention, the seal ring 30 is electrically coupled to the lower substrate 101 via a through contact TV penetrating the device layer 103 and the buried oxide layer 102.

According to an embodiment of the present invention, the two adjacent dielectric films 401 and 403 are two adjacent low-k dielectric films. According to an embodiment of the present invention, the integrated circuit device 1 further includes: an uppermost dielectric film 405 covering the dielectric stack 40; a top via hole Vn penetrating the top dielectric film 405 and the moisture barrier layer 404 to electrically connect to the top copper metal line M2; and an aluminum pad AP, which is arranged on the top layer interlayer through hole Vn and is electrically connected with the top layer interlayer through hole Vn.

According to an embodiment of the present invention, the passivation layer PL covers the periphery of the aluminum pad AP and the top surface of the uppermost dielectric film 405. In accordance with an embodiment of the present invention, the uppermost dielectric film 405 comprises silicon oxide. According to an embodiment of the present invention, the passivation layer PL includes polyimide, silicon nitride or silicon oxide. According to an embodiment of the present invention, the moisture barrier layer 404 comprises silicon nitride, silicon oxynitride or silicon carbonitride.

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.