CN105984836B - MEMS device and manufacturing method thereof - Google Patents
MEMS device and manufacturing method thereof Download PDFInfo
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- CN105984836B CN105984836B CN201510084495.5A CN201510084495A CN105984836B CN 105984836 B CN105984836 B CN 105984836B CN 201510084495 A CN201510084495 A CN 201510084495A CN 105984836 B CN105984836 B CN 105984836B
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Abstract
The invention provides an MEMS device and a manufacturing method thereof, wherein the method comprises the following steps: providing a MEMS wafer, and forming a patterned device layer on the front surface of the MEMS wafer; forming a buffer layer with an opening on the front surface of the MEMS wafer, wherein the thickness of the buffer layer is larger than that of the patterned device layer, and the opening exposes the patterned device layer; forming a protective layer on the buffer layer, wherein a bottom of the protective layer is not in contact with a top of the patterned device layer; and reversing the MEMS wafer to execute a back process. According to the manufacturing method, the adhesive surface of the adhesive tape serving as the protective layer is not in contact with the patterned device layer, so that the patterned device layer is not affected in the process of removing the adhesive tape, the phenomenon that an MEMS device is damaged in the process of removing the adhesive tape (tape) is improved, the device is protected, and the performance and the yield of the MEMS device are improved.
Description
Technical Field
The invention relates to the technical field of semiconductors, in particular to an MEMS (micro-electromechanical system) device and a manufacturing method thereof.
Background
With the continuous development of semiconductor technology, smart phones, integrated CMOS and micro-electro-mechanical systems (MEMS) devices are increasingly becoming the most mainstream and advanced technology in the market of sensor-like products, and with the updating of technology, the development direction of such transmission sensor products is smaller scale, high quality electrical performance and lower loss.
Among them, MEMS sensors are widely used in automotive electronics: such as TPMS, engine oil pressure sensor, automobile brake system air pressure sensor, automobile engine intake manifold pressure sensor (TMAP), diesel engine common rail pressure sensor; consumer electronics: such as a tire pressure meter, a sphygmomanometer, a kitchen scale, a health scale, a pressure sensor for a washing machine, a dish washing machine, a refrigerator, a microwave oven, an oven and a dust collector, an air conditioner pressure sensor, a liquid level control pressure sensor for a washing machine, a water dispenser, a dish washing machine and a solar water heater; industrial electronics: such as digital pressure gauge, digital flow meter, industrial ingredient weighing, etc.
In the field of MEMS, the operating principle of the MEMS device is that a capacitance change is generated by a movement of a vibrating Membrane (Membrane), and the capacitance change is used for operation and working, and due to the functional requirements of the device, a process needs to be performed on both the front and back sides of a wafer to form a functional device, in order to protect the device on the front side of the wafer in the current MEMS device manufacturing process, a tape protection (tape) is often added, but it is often found that the MEMS device is directly adhered by the viscosity of the tape (tape) in the tape (tape) removing process, and a Yield (Yield) loss is caused.
There is therefore a need for further improvements in the current methods of manufacturing MEMS devices in order to eliminate the various drawbacks mentioned above.
Disclosure of Invention
In this summary, concepts in a simplified form are introduced that are further described in the detailed description. This summary of the invention is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
In order to overcome the existing problems, an embodiment of the present invention provides a method for manufacturing a MEMS device, including:
step S1: providing a MEMS wafer, and forming a patterned device layer on the front surface of the MEMS wafer;
step S2: forming a buffer layer with an opening on the front surface of the MEMS wafer, wherein the thickness of the buffer layer is larger than that of the patterned device layer, and the opening exposes the patterned device layer;
step S3, forming a protective layer on the buffer layer, wherein the protective layer covers the buffer layer and the opening, and the bottom of the protective layer is not in contact with the top of the patterned device layer;
step S4: and reversing the MEMS wafer to execute a back process.
Further, the buffer layer is made of photoresist.
Further, the step of forming the buffer layer includes: and forming a photoresist on the front surface of the MEMS wafer, and exposing and developing the photoresist covering the patterned device layer to form an opening for exposing the patterned device layer.
Further, in the step S3, the protective layer is an adhesive tape.
Further, the backside process comprises: and etching the back surface of the MEMS wafer in the area corresponding to the patterned device layer until part of the bottom surface of the patterned device layer is exposed so as to form a back hole.
Further, the method still further comprises:
step S5: inverting the MEMS wafer again to enable the front side of the MEMS wafer to face upwards;
step S6: and sequentially removing the protective layer and the buffer layer on the front surface of the MEMS wafer.
Further, the patterned device layer is correspondingly located in a uPhone area of the MEMS wafer, and the opening exposes the uPhone area.
The second embodiment of the invention provides an MEMS device manufactured and obtained based on the method.
In summary, according to the manufacturing method of the present invention, since the adhesive surface of the adhesive tape serving as the protective layer is not in contact with the patterned device layer, the patterned device layer is not affected in the process of removing the adhesive tape, so that the phenomenon that the MEMS device is damaged in the process of removing the adhesive tape (tape) is improved, the device is protected, and the performance and yield of the MEMS device are improved.
Drawings
The following drawings of the invention are included to provide a further understanding of the invention. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
In the drawings:
FIGS. 1A-1F are schematic diagrams illustrating a prior art MEMS device fabrication process;
FIG. 1G shows a scanning electron microscope image on the left when the MEMS device is unaffected and on the right after the MEMS device is taped away;
FIGS. 2A-2G show schematic cross-sectional views of a MEMS device obtained by sequential implementation of the fabrication method according to the invention;
fig. 3 shows a process flow diagram of sequential implementation steps of a fabrication method according to the invention.
Detailed Description
In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.
It is to be understood that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Like reference numerals refer to like elements throughout.
It will be understood that when an element or layer is referred to as being "on" …, "adjacent to …," "connected to" or "coupled to" other elements or layers, it can be directly on, adjacent to, connected to or coupled to the other elements or layers or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on …," "directly adjacent to …," "directly connected to" or "directly coupled to" other elements or layers, there are no intervening elements or layers present. It will be understood that, although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention.
Spatial relationship terms such as "under …", "under …", "below", "under …", "above …", "above", and the like, may be used herein for ease of description to describe the relationship of one element or feature to another element or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, then elements or features described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary terms "below …" and "below …" can encompass both an orientation of up and down. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatial descriptors used herein interpreted accordingly.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of the associated listed items.
In order to provide a thorough understanding of the present invention, detailed steps will be set forth in the following description in order to explain the technical solutions proposed by the present invention. The following detailed description of the preferred embodiments of the invention, however, the invention is capable of other embodiments in addition to those detailed.
At present, as shown in fig. 1A-1F, a method for manufacturing a MEMS device includes first providing a MEMS wafer 101, and forming a patterned device layer 102 on a front surface of the MEMS wafer 101, as shown in fig. 1A; next, forming a tape (tape)104 on the front surface of the MEMS wafer 101, wherein in order to prevent the residual glue of the tape (tape)104 from being removed easily, a photoresist 103 is formed between the tape (tape)104 and the MEMS wafer 101 as an intermediate layer, and the photoresist 103 and the residual glue on the photoresist 103 are removed by a photoresist stripping (PR Strip) manner, so as to avoid that the residual glue stays on the MEMS device and affects the device performance, as shown in fig. 1B-1C.
The MEMS wafer 101 is then inverted so that its backside faces upward, a backside process is performed, forming a backside hole 105 in the backside of the MEMS wafer 101, where the backside hole is located corresponding to the patterned device layer 102 and exposes a portion of the backside of the patterned device layer 102. As shown in fig. 1D.
The MEMS wafer 101 is again inverted so that it is right side up, as shown in fig. 1E.
Finally, as shown in fig. 1F, the adhesive tape 104 is removed, and the MEMS device 102 in the area corresponding to the position of the groove is easily taken away when the adhesive tape is peeled off during the process of removing the adhesive tape 104, so that the performance of the MEMS device is reduced and even the MEMS device fails. Fig. 1G shows a scanning electron microscope image on the left when the MEMS device is unaffected and on the right after the MEMS device is taped away.
Therefore, further improvements to the presently described methods are needed to eliminate the various problems described above.
Example one
Next, a method of manufacturing the MEMS device of the present invention will be described in detail with reference to fig. 2A to 2G and fig. 3.
First, referring to fig. 2A, a MEMS wafer 201 is provided, and a patterned device layer 202 is formed on a front surface of the MEMS wafer 201.
Wherein the MEMS wafer 201 comprises at least a semiconductor substrate, which may be at least one of the following materials: silicon, silicon-on-insulator (SOI), silicon-on-insulator (SSOI), silicon-on-insulator-silicon-germanium (S-SiGeOI), silicon-on-insulator-silicon-germanium (SiGeOI), and germanium-on-insulator (GeOI), among others. An active region may be defined on the semiconductor substrate.
The patterned device layer 202 may be used as a diaphragm or a backplate of a MEMS device, but is not limited to this example. The patterned device layer 202 may be formed by first depositing a device material layer, such as a diaphragm, a backplate, or other materials, on the front surface of the MEMS wafer 201, then forming a patterned photoresist layer on the device material layer, and etching the device material layer using the photoresist layer as a mask to form the patterned device layer 202. Illustratively, the patterned device layer corresponds to a uhphone area of the MEMS wafer.
Next, referring to fig. 2C, wherein the left drawing in fig. 2C is a cross-sectional view of the device and the right drawing is a partial top view of the device, a buffer layer 203 having an opening 2031 is formed on the front surface of the MEMS wafer 201, wherein the thickness of the buffer layer 203 is greater than that of the patterned device layer 202, and the opening 2031 exposes the patterned device layer 202.
Illustratively, the material of the buffer layer is photoresist. The material of the photoresist may include a group of positive photoresist, negative photoresist, or hybrid photoresist.
In one example, when the material of the buffer layer is photoresist, the method of forming the buffer layer includes: as shown in the left diagram of fig. 2B, a photoresist 203a is formed on the front surface of the MEMS wafer 201, where the left diagram of fig. 2B is a partial cross-sectional view of the MEMS wafer, the right diagram is a partial top view of the MEMS wafer, and the patterned device layer in the left diagram is correspondingly located in the main chip area in the right diagram, and in one example, when the MEMS device is a uPhone device, the patterned device layer is correspondingly located in the uPhone area. As shown in the left view of fig. 2C, the photoresist covering the patterned device layer 202 is exposed and developed to form an opening 2031 exposing the patterned device layer 202. As can be seen from the right view of fig. 2C, the photoresist in the main chip region may also be exposed and developed to form a photoresist 203 with an opening exposing the main chip region. Exemplarily, when the MEMS device is a uPhone device, the photoresist in the uPhone region may be exposed and developed to form an opening exposing the uPhone region.
Next, referring to fig. 2D, a protective layer 204 is formed on the buffer layer 203, wherein a bottom of the protective layer 204 is not in contact with a top of the patterned device layer 202.
Specifically, in this step, a protection layer 204 is formed on the buffer layer 203, the protection layer 204 directly contacts the buffer layer 203 on both sides of the opening 2031 and does not contact the patterned device layer 202 in the opening 2031, and since the thickness of the buffer layer 203 is greater than that of the patterned device layer 202, a certain distance is formed between the bottom of the protection layer 204 and the top of the MEMS pattern to form a certain interval, so as to prevent the protection layer 204 from contacting the patterned device layer 202.
Optionally, the protective layer 204 is an adhesive tape. The adhesive tape may be a blue tape or a uv tape, and the adhesive tape may be attached on the buffer layer 203 by a direct attachment method.
Next, referring to fig. 2E, the MEMS wafer 201 is inverted, and a back process is performed.
Specifically, the MEMS wafer 201 is inverted such that the MEMS wafer has a front side facing down and a back side facing up, wherein the protective layer 204 can protect the patterned device layer 202 from damage while not contacting the patterned device layer 202.
A backside process is then performed. In one example, the backside process comprises: the back side of the MEMS wafer 201 in the area corresponding to the patterned device layer 202 is etched until a portion of the bottom surface of the patterned device layer 202 is exposed to form a back hole 205.
In this embodiment, the C-F etchant, which is CF, is preferably selected for etching4、CHF3、C4F8And C5F8One or more of (a). In this embodiment, the dry etching may be CF4、CHF3In addition, N is added2、CO2As an etching atmosphere, wherein the gas flow rate is CF410-200sccm，CHF310-200sccm，N2Or CO2Or O210-400sccm, the etching pressure is 30-150mTorr, and the etching time is 5-120 s.
In the field of MEMS, the working principle of a capacitive MEMS device is that a diaphragm (Membrane) moves to generate a capacitance change, and the capacitance change is used for operation and work.
In another example, various functional patterns and/or devices may also be formed on the back side of the MEMS wafer, wherein the various functional patterns and/or devices are not limited to a certain type and are selected according to the requirements of the MEMS device.
Referring to fig. 2F, the MEMS wafer 201 is inverted again so that the MEMS wafer 201 is right side up.
Next, referring to fig. 2G, the protection layer 204 and the buffer layer 203 on the front surface of the MEMS wafer 201 are sequentially removed.
In one example, when the protective layer 204 is an adhesive tape, the protective layer can be removed by directly peeling off the adhesive tape by a film peeling machine, which is only an example, and an appropriate removing method can be selected according to the material of the protective layer. Because the protective layer 203 is not in contact with the patterned device layer 202, and a buffer layer does not exist between the device layer 202 and the protective layer 203, the patterned device layer 202 is not adhered together when the protective layer is removed, and thus, the MEMS device is not damaged.
The buffer layer (e.g., photoresist) can be removed by any method known to those skilled in the art, such as ashing, etc.
Thus, the description of the steps related to the fabrication of the MEMS device according to the embodiment of the present invention is completed. After the above steps, other related steps may also be included, which are not described herein again. Besides the above steps, the manufacturing method of this embodiment may further include other steps in the above steps or between different steps, and these steps may be implemented by various processes in the prior art, and are not described herein again.
In summary, according to the manufacturing method of the present invention, since the adhesive surface of the adhesive tape serving as the protective layer is not in contact with the patterned device layer, the patterned device layer is not affected in the process of removing the adhesive tape, so that the phenomenon that the MEMS device is damaged in the process of removing the adhesive tape (tape) is improved, the device is protected, and the performance and yield of the MEMS device are improved.
Referring to fig. 3, a process flow diagram illustrating the steps performed in sequence for one embodiment of the present invention is shown to schematically illustrate the flow of the overall fabrication process.
In step 301, providing a MEMS wafer, wherein a patterned device layer is formed on a front surface of the MEMS wafer;
in step 302, a buffer layer with an opening is formed on the front side of the MEMS wafer, wherein the thickness of the buffer layer is greater than the thickness of the patterned device layer, and the opening exposes the patterned device layer;
in step 303, forming a protective layer on the buffer layer, wherein a bottom of the protective layer is not in contact with a top of the patterned device layer;
in step 304, the MEMS wafer is inverted and a backside process is performed;
in step 305, the MEMS wafer is inverted again so that the front side of the MEMS wafer is facing up;
in step 306, the protective layer and the buffer layer on the front side of the MEMS wafer are sequentially removed.
Example two
The invention further provides an MEMS device which is manufactured by the method in the first embodiment.
Because the manufacturing method has excellent technical effects, the MEMS device manufactured by the method does not have the loss of device layer patterns, and therefore the semiconductor device formed by the manufacturing method has higher performance and reliability.
The present invention has been illustrated by the above embodiments, but it should be understood that the above embodiments are for illustrative and descriptive purposes only and are not intended to limit the invention to the scope of the described embodiments. Furthermore, it will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that many variations and modifications may be made in accordance with the teachings of the present invention, which variations and modifications are within the scope of the present invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (4)
1. A method of fabricating a MEMS device, comprising:
step S1: providing a MEMS wafer, and forming a patterned device layer on the front surface of the MEMS wafer;
step S2: forming a buffer layer with an opening on the front surface of the MEMS wafer, wherein the buffer layer is made of photoresist, the thickness of the buffer layer is greater than that of the patterned device layer, and the opening exposes the patterned device layer;
step S3: forming a protective layer on the buffer layer, wherein the protective layer is made of an adhesive tape, the protective layer is adhered to the buffer layer by a direct adhering method, the protective layer covers the buffer layer and the opening, and the bottom of the protective layer is not in contact with the top of the patterned device layer;
step S4: reversing the MEMS wafer and executing a back process;
step S5: inverting the MEMS wafer again to enable the front side of the MEMS wafer to face upwards;
step S6: and sequentially removing the protective layer and the buffer layer on the front surface of the MEMS wafer, wherein the protective layer is removed by directly removing the protective layer by using a film removing machine, and the photoresist is removed by using an ashing method.
2. The method of claim 1, wherein the step of forming the buffer layer comprises: and forming a photoresist on the front surface of the MEMS wafer, and exposing and developing the photoresist covering the patterned device layer to form an opening for exposing the patterned device layer.
3. The method of claim 1, wherein the backside process comprises: and etching the back surface of the MEMS wafer in the area corresponding to the patterned device layer until part of the bottom surface of the patterned device layer is exposed so as to form a back hole.
4. The method of claim 1, wherein the patterned device layer is located corresponding to a uPhone region of the MEMS wafer, and the opening exposes the uPhone region.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7008821B1 (en) * | 2004-09-10 | 2006-03-07 | Touch Micro-System Technology Inc. | Method of forming a wafer backside interconnecting wire |
| CN101086956A (en) * | 2006-06-09 | 2007-12-12 | 松下电器产业株式会社 | Method for fabricating semiconductor device |
| CN101820570A (en) * | 2006-10-13 | 2010-09-01 | 欧姆龙株式会社 | Microphone |
| CN104118844A (en) * | 2014-07-15 | 2014-10-29 | 电子科技大学 | Method for thinning silicon-base back surface |
| CN104340955A (en) * | 2014-09-12 | 2015-02-11 | 华中科技大学 | Preparation method of micro Pirani gauge and method for integrally processing bulk-silicon device together with micro Pirani gauge |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2455332B1 (en) * | 2010-11-19 | 2014-02-12 | Imec | Method for producing temporary cap on a MEMS device |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7008821B1 (en) * | 2004-09-10 | 2006-03-07 | Touch Micro-System Technology Inc. | Method of forming a wafer backside interconnecting wire |
| CN101086956A (en) * | 2006-06-09 | 2007-12-12 | 松下电器产业株式会社 | Method for fabricating semiconductor device |
| CN101820570A (en) * | 2006-10-13 | 2010-09-01 | 欧姆龙株式会社 | Microphone |
| CN104118844A (en) * | 2014-07-15 | 2014-10-29 | 电子科技大学 | Method for thinning silicon-base back surface |
| CN104340955A (en) * | 2014-09-12 | 2015-02-11 | 华中科技大学 | Preparation method of micro Pirani gauge and method for integrally processing bulk-silicon device together with micro Pirani gauge |
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