KR102153485B1 - gas sensor package, gas sensor wafer level package, and the method for manufacturing the same - Google Patents

Abstract

A gas sensor package according to an embodiment of the present invention is a gas sensor package using a wafer level package process, comprising: a semiconductor substrate; A redistribution layer provided on the semiconductor substrate and electrically connected to the sensing layer to transmit a gas sensing signal; A passivation layer provided to cover the redistribution layer; A sensing layer provided to be exposed on the passivation layer to detect gas; And a plurality of connection electrodes electrically connected to the redistribution layer and provided to be exposed on the passivation layer so as to be connectable to external terminals.

Description

Gas sensor package, gas sensor wafer level package, and the manufacturing method thereof {gas sensor package, gas sensor wafer level package, and the method for manufacturing the same}

The present invention relates to a gas sensor package, a gas sensor wafer level package, and a method of manufacturing the same, and more particularly, a gas sensor package having a structure capable of simple manufacturing while improving a protection function for a sensing layer, a gas sensor wafer level package, and It relates to the manufacturing method.

Gas sensors that detect gas are classified into semiconductor type, vibrator type, solid electrolyte type, and contact combustion type according to their operating principle. Among them, a semiconductor type gas sensor is generally used, and the semiconductor type gas sensor detects the gas by using the principle that changes in electrical resistance, current, work function, etc. occur when a specific gas contacts the sensing layer. These semiconductor-type gas sensors are manufactured in the form of a package (hereinafter, a semiconductor-type gas sensor package is referred to as “gas sensor package”). It is easy to manufacture due to its simple configuration, can detect various gases, and has stable characteristics at room temperature. There are several advantages, such as indicating.

1 is a cross-sectional view of a conventional first gas sensor package mounted on a printed circuit board (PCB).

Meanwhile, as shown in FIG. 1, the conventional first gas sensor package includes a semiconductor substrate S, a sensing layer MR, an upper/lower passivation layer P _T , P _B , a redistribution layer RDL, It includes a bonding wire (BW), a connection electrode (CE), and a molding member (MO).

At this time, the lower passivation layer P _B is provided to cover the lower portion of the semiconductor substrate S, and the sensing layer MR is provided to be exposed to the outside on the semiconductor substrate S to detect the deduction by contacting the gas, and The wiring layer RDL is covered by the upper passivation layer P _T on the semiconductor substrate S, but is provided to be electrically connected to the sensing layer MR to transmit a gas detection signal. In addition, the connection electrode CE is an electrode provided to be exposed to the outside to be connected to an external terminal such as a printed circuit board (PCB), and is electrically connected to the redistribution layer RDL by a bonding wire BW, and a molding member (MO) is provided to cover the above-described components with an epoxy mold compound (EMC) or the like so that the above-described components are not exposed to the outside.

However, the conventional first gas sensor package has a problem in that the manufacturing process efficiency decreases and the thickness of the entire package increases as the bonding wire (BW) and the molding member (MO) are provided.

2 is a cross-sectional view of a conventional second gas sensor package mounted on a printed circuit board (PCB).

In order to solve this problem, the conventional second gas sensor package further includes a through electrode TSV and a cap replacing the bonding wire BW and the molding member MO, as shown in FIG. 2. Include. At this time, the through electrode TSV is provided so as to penetrate the semiconductor substrate S to electrically connect the redistribution layer RDL and the connection electrode CE, and the cap CAP is on the upper passivation layer P _T Bonding (hereinafter referred to as “capping process”) protects the remaining components of the package.

However, the conventional second gas sensor package only increases the time and cost of the manufacturing process because the through part (CV) through which gas is introduced must be formed in the cap and the bonding process of the cap must be performed separately. In addition, since the bonding process of the cap must be performed after forming the detection layer MR, there is a problem in that the detection layer MR may be damaged during the bonding process of the cap. In addition, since the conventional second gas sensor package has a structure in which the sensing layer MR is exposed to the outside when mounted on a printed circuit board (PCB), etc., the sensing layer MR can be easily damaged by an external environment. There is a problem. In addition, these problems also occur in the conventional first gas sensor package.

In order to solve the problems of the prior art as described above, the present invention provides a gas sensor package, a gas sensor wafer level package, and a manufacturing method thereof having a structure that can be easily manufactured while improving the protection function for the sensing layer. There is this.

However, the problem to be solved by the present invention is not limited to the problems mentioned above, and other problems that are not mentioned will be clearly understood by those skilled in the art from the following description.

The gas sensor package according to an embodiment of the present invention for solving the above problems is a gas sensor package using a wafer level package process, which is provided on (1) a semiconductor substrate, (2) a semiconductor substrate, and is provided on a sensing layer. A redistribution layer that is electrically connected to transmit a gas detection signal, (3) a passivation layer provided to cover the redistribution layer, (4) a detection layer provided to be exposed on the passivation layer to detect gas, and (5) the redistribution layer electrically It is connected, and includes a plurality of connection electrodes provided to be exposed on the passivation layer so as to be connectable to external terminals.

The passivation layer may have a stepped portion formed in a stepped shape, and the sensing layer may be provided in the stepped portion.

Each of the connection electrodes may be provided on a passivation layer region around the stepped portion, and the stepped portion may be provided between the connection electrodes.

The connection electrode may include (1) an under bump metal layer that is electrically connected to the redistribution layer and exposed on the passivation layer, (2) an under bump metal layer that is electrically connected to the under bump metal layer, and is provided on the under bump metal layer. .

The connection electrode includes (1) a Cu post that is electrically connected to the redistribution layer and has a predetermined height while being exposed on the passivation layer, and (2) is electrically connected to the Cu post, and includes a solder cap provided on the Cu post. I can.

A gas sensor package according to an embodiment of the present invention includes the semiconductor substrate, the redistribution layer, the passivation layer, the sensing layer, and the connection electrode, respectively, but having different sensing layers and a plurality of gases arranged to be stacked with each other. The first gas sensor package may include a sensor package, and the first gas sensor package stacked on top of the second gas sensor package penetrates its own semiconductor substrate and is electrically connected to its own redistribution layer and the connection electrode of the second gas sensor structure. It may further include a through electrode.

A gas sensor package according to an embodiment of the present invention includes a plurality of gas sensor structures each having the redistribution layer, the passivation layer, the sensing layer, and the connection electrode, but having different sensing layers and arranged in parallel with each other. Each gas sensor structure may include the semiconductor substrate that is used in common with each other.

The gas sensor wafer level package according to an embodiment of the present invention includes (1) a semiconductor wafer, (2) a redistribution layer provided on the semiconductor wafer and electrically connected to the sensing layer to transmit a gas detection signal, (3) A passivation layer provided to cover the redistribution layer, (4) a sensing layer provided to be exposed on the passivation layer to detect gas, (5) electrically connected to the redistribution layer, and provided to be exposed on the passivation layer to be connected to an external terminal. It includes a plurality of connection electrodes.

A method of manufacturing a gas sensor package according to an embodiment of the present invention includes (a) preparing a semiconductor wafer, (b) a redistribution layer provided on the semiconductor wafer and transmitting a gas detection signal, and a redistribution layer provided to cover the redistribution layer. Forming a passivation layer and a plurality of connection electrodes electrically connected to the redistribution layer and exposed on the passivation layer to enable connection to external terminals, (c) electrically connected to the redistribution layer and exposed on the passivation layer Forming a sensing layer that senses a gas that is provided as possible, and (d) cutting each gas sensor package including a semiconductor substrate, a redistribution layer, a passivation layer, a sensing layer, and a connection electrode.

Step (b) may include forming a passivation layer having a stepped portion having a stepped shape, and step (c) may include forming a sensing layer in the stepped portion.

The step (b) may include forming a stepped portion between the connection electrodes, and forming each connection electrode on the passivation layer region around the stepped portion.

A method of manufacturing a gas sensor package according to an embodiment of the present invention may further include (e) stacking a plurality of gas sensor packages having different sensing layers on each other.

The step (b) may further include forming a through electrode that penetrates the semiconductor substrate and is electrically connected to the redistribution layer, and the step (e) includes a first gas stacked on the second gas sensor package. It may further include electrically connecting the through electrode of the sensor package to the connection electrode of the second gas sensor package.

The step (c) may include forming a plurality of different sensing layers within the region of each gas sensor package, and the step (d) is arranged in parallel with each other and provided with different sensing layers, It may include cutting each gas sensor package such that a plurality of gas sensor structures using a semiconductor substrate are included in each gas sensor package. In this case, each of the gas sensor structures may include a common semiconductor base, a redistribution layer, a passivation layer, a sensing layer, and a connection electrode.

In the gas sensor package, gas sensor wafer level package, and manufacturing method according to an embodiment of the present invention configured as described above, when the gas sensor package is mounted on a printed circuit board (PCB), the semiconductor substrate is exposed to the outside, At the same time, since the sensing layer is positioned inside the semiconductor substrate, the semiconductor substrate has an advantage of having a structure of a protective function capable of naturally protecting the sensing layer from external impact or external contact.

In addition, in the gas sensor package, the gas sensor wafer level package, and the manufacturing method according to an embodiment of the present invention, as a step portion is formed in the passivation layer, a peripheral passivation layer region other than the step portion is disposed to surround the sensing layer, There is an advantage that the protection function can be further strengthened.

In addition, since the gas sensor package, the gas sensor wafer level package, and the manufacturing method according to an embodiment of the present invention have a structure in which a sensing layer is provided in the stepped portion of the passivation layer, the basic structure of the redistribution layer, electrode pad, passivation layer, Since the sensing layer can be formed after each connection electrode is formed, there is an advantage of preventing damage to the sensing layer that may occur during the formation of the basic structure.

In addition, since the gas sensor package, the gas sensor wafer level package, and the manufacturing method according to an embodiment of the present invention are manufactured through a wafer level packaging process, processes such as a molding process, a capping process, and a through part formation process during the capping process As can be omitted, there is an advantage in that cost can be reduced and the process can be simplified.

1 is a cross-sectional view of a conventional first gas sensor package mounted on a printed circuit board (PCB).
2 is a cross-sectional view of a conventional second gas sensor package mounted on a printed circuit board (PCB).
3 to 9 are cross-sectional views of gas sensor packages according to the first to seventh embodiments of the present invention mounted on a printed circuit board (PCB).
10 is a flowchart illustrating a method of manufacturing a gas sensor package according to an embodiment of the present invention.
11 shows a preparation step (S10) of a method for manufacturing a gas sensor package according to an embodiment of the present invention.
12 shows a basic structure forming step (S20) of a method for manufacturing a gas sensor package according to an embodiment of the present invention.
13 shows a step (S30) of forming a sensing layer in a method of manufacturing a gas sensor package according to an embodiment of the present invention.
14 shows a cutting step (S40) of a method for manufacturing a gas sensor package according to an embodiment of the present invention.

The above objects and means of the present invention, and effects thereof, will become more apparent through the following detailed description in connection with the accompanying drawings, and accordingly, a person having ordinary knowledge in the technical field to which the present invention belongs can facilitate the technical idea of the present invention. It will be possible to do it. In addition, in describing the present invention, when it is determined that a detailed description of known technologies related to the present invention may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted.

In addition, terms used in the present specification are for describing embodiments, and are not intended to limit the present invention. In the present specification, the singular form also includes the plural form in some cases, unless specifically stated in the phrase. Terms such as "to include", "to have", "to prepare" or "have" used in the specification do not exclude the presence or addition of one or more other elements other than the mentioned elements.

In the present specification, expressions such as “or” and “at least one” may represent one of words listed together, or a combination of two or more. For example, “or B” “at least one of “and B” may include only one of A or B, and may include both A and B.

In this specification, descriptions according to expressions such as "for example" may not exactly match the information presented, such as a recited characteristic, variable, or value, and are usually limited to tolerances, measurement errors, and measurement accuracy. Embodiments of the invention according to various embodiments of the present invention should not be limited to effects such as modifications including other known factors.

In the present specification, when a component is referred to as being'connected' or'connected' to another component, it may be directly connected or connected to the other component, but the other component is It should be understood that it may exist. On the other hand, when a component is referred to as being'directly connected' or'directly connected' to another component, it should be understood that there is no other component in the middle.

Unless otherwise defined, all terms used in the present specification may be used as meanings that can be commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not interpreted ideally or excessively unless explicitly defined specifically.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, for convenience of explanation, the upper and lower portions shown in the drawings will be interchanged and described.

First, a gas sensor package according to various embodiments of the present disclosure will be described.

3 is a cross-sectional view of a gas sensor package according to a first embodiment of the present invention mounted on a printed circuit board (PCB).

A gas sensor package using the gas sensor wafer level package process according to the first embodiment of the present invention, as shown in FIG. 3, a semiconductor substrate 1, a redistribution layer 2, an electrode pad 3, and a passivation layer (4), a sensing layer 5 and a connection electrode 6 are included.

The semiconductor substrate 1 may be made of single crystal silicon or polycrystalline silicon, but is not limited thereto.

In particular, when the gas sensor package is mounted on a printed circuit board (PCB), the semiconductor substrate 1 is exposed to the outside, and at the same time, the sensing layer 5 is located inside the semiconductor substrate 1. Accordingly, the semiconductor substrate 1 may naturally protect the sensing layer 5 from external impact, external contact, etc. (hereinafter referred to as “protective function”).

Meanwhile, the semiconductor substrate 1 may also include an integrated circuit. For example, the semiconductor substrate 1 is a semiconductor memory device (DRAM, SRAM, Flash memory, etc.), a processor device (CPU, DSP, etc.), ASIC (Application Specific Integrated Circuit) device, MEMS (Micro Electro Mechanical System) device, Various integrated circuits for forming photoelectric devices, light emitting devices, and various filter devices may be included, but are not limited thereto.

The redistribution layer (RDL) is provided on the semiconductor substrate 1 but is provided inside the passivation layer 4 and is electrically connected to the sensing layer 5 to occur in the sensing layer 5 Transmitted gas detection signal.

The electrode pad 3 is provided on the semiconductor substrate 1 and is a part to which a gas detection signal is output by being electrically connected. For example, the electrode pad 3 may be made of a metal having a low specific resistance such as aluminum (Al), copper (Cu), platinum (Pt), or the like. In FIG. 3, two electrode pads 3 are shown, but the number of electrode pads 3 is not limited thereto, and a plurality of electrode pads 3 may be provided.

The passivation layer 4 is provided to cover the redistribution layer 2, and the semiconductor substrate 1, the redistribution layer 2, the electrode pad 3, the sensing layer 5 and the connection electrode 6 It prevents unnecessary electrical shorts between, and prevents physical/chemical damage to these components from the outside.

In addition, the passivation layer 4 may include a plurality of layers 41, 42, 43, 44. In this case, the first passivation layer 41 is stacked on the top surface of the semiconductor substrate 1, and the second passivation layer 42 is stacked on the top surface of the first passivation layer 41. Likewise, the third passivation layer 43 is stacked on the top surface of the second passivation layer 42, and the fourth passivation layer 44 is stacked on the top surface of the third passivation layer 43. The redistribution layer 2 may be provided between the first passivation layer 41 to the third passivation layer 43, and the electrode pad 3 may be provided to be exposed from the third passivation layer 43, It is not limited thereto.

Meanwhile, the passivation layer 4 may be made of an insulating material. For example, the passivation layer 4 may be made of a polymer material. That is, the passivation layer 4 is a general-purpose polymer such as PMMA (Polymethylmethacrylate), PS (Polystylene), PBO (Polybenzoxzaoles), acrylic polymer, imide polymer, aryl ether polymer, amide polymer, fluorine polymer, p-xyl It may include a rene-based polymer, a vinyl alcohol-based polymer, a polymer derivative having a phenolic group, and the like, but is not limited thereto. Further, the first passivation layer 41 may be formed of an inorganic insulating material such as a silicon oxide layer or a silicon nitride layer, but is not limited thereto.

The sensing layer 5 (Membrane) is a layer that senses gas, and is provided to be exposed on the passivation layer 4. In this case, the sensing layer 5 may include a material that changes in electrical resistance, current, and work function when gas is adsorbed.

For example, the sensing layer 5 contains metal oxides (M _x O _y ), gold nanoparticles, graphene, carbon nanotubes, fullerenes, molybdenum disulfide (MoS ₂ ), etc. It may include, but is not limited thereto. At this time, the metal oxide (M _x O _y ) is cobalt oxide (CoO _x ), gallium oxide (GaO _x ), indium oxide (InO _x ), tin oxide (SnO _x ), titanium oxide (TiO _x ), tungsten oxide (WO). _x ), zinc oxide (ZnO _x ), and the like, but are not limited thereto.

In addition, the sensing layer 5 may include a sensing electrode that generates a change signal such as electric resistance, current, and work function according to gas adsorption, that is, a gas sensing signal. In this case, the sensing electrode may be electrically connected to the redistribution layer 2. However, when there is no sensing electrode, the redistribution layer 2 may be provided to replace the role of the sensing electrode.

In particular, the sensing layer 5 is preferably provided in the step portion 40 of the passivation layer 4. That is, the passivation layer 4 may include a stepped portion 40 having a stepped shape, and in this case, the sensing layer 5 is provided in the stepped portion 40, so that the peripheral passivation layer 4 other than the stepped portion 40 is provided. ) Area may be arranged to surround the sensing layer 5. Accordingly, there is an advantage that the protective function for the sensing layer 5 can be further strengthened.

For example, the third passivation layer 43 and the fourth passivation layer 44 may each have a groove, and the groove of the third passivation layer 43 is wider than the groove of the fourth passivation layer 44. By being formed small, the step portion 40 may be provided. Of course, grooves may also be provided in the second passivation layer 42, and in this case, the grooves of the second passivation layer 42 have a width greater than that of the third passivation layer 43 or the fourth passivation layer 44. It can be formed small. In this case, the sensing layer 5 may be provided to contact the lower portion of the step portion 40, that is, the bottom surface of the widest groove.

A plurality of connection electrodes 6 are provided so as to be exposed on the passivation layer 4 so as to be connected to external terminals such as a printed circuit board (PCB). At this time, the connection electrode 6 is electrically connected to the electrode pad 3, that is, the redistribution layer 2 to transmit a gas detection signal to an external terminal.

In particular, each of the electric flux electrodes 6 is preferably provided in the region of the passivation layer 4 around the step portion 40 other than the step portion 40, that is, on the fourth passivation layer 44, which is the uppermost passivation layer 4 Do. In this case, since the step portion 40 is disposed between the connection electrodes 6, when the gas sensor package is mounted on an external device such as a printed circuit board (PCB), the sensing layer provided in the step portion 40 ( 5) is disposed to face the external device, and thus, the protective function of the sensing layer 5 may be enhanced.

For example, the connection electrode may include an under bump metal layer 61 and bump 62.

The under bump metallurgy is a configuration for improving the connection reliability of the bumps 61, and on the passivation layer 4, that is, the fourth passivation layer 44, which is the uppermost passivation layer 4 It is provided to be exposed, but is provided on the electrode pad 3 and is electrically connected to the redistribution layer 2. That is, the under bump metal layer 61 provides a wetting layer to facilitate adhesion of the bumps 62 and at the same time prevents penetration of the bumps 62.

The under bump metal layer 61 may be formed by a metallization method using a known metal, and may be configured in various forms. For example, the under bump metal layer 61 may be formed of Cu, Cu/Ni, Cu/Ni/Au, Cr/Cr-Cu/Cu, TiW/Cu, Al/NiV/Cu, etc., but is limited thereto. no.

The bump 62 is a conductive protrusion for directly contacting an external terminal such as a printed circuit board (PCB), and is provided on the under bump metal layer 61 and is electrically connected to the under bump metal layer 61. The bump 62 is provided to be exposed on the uppermost passivation layer 4 without the under bump metal layer 61 but is provided on the electrode pad 3 and may be electrically connected to the redistribution layer 2. The bump 62 is in the form of a solder ball, a metal core ball, or a plastic core ball, and may have a spherical shape, an egg shape, or a cubic shape, and may be a stud bump ( Stud Bump) form, but is not limited thereto.

The solder ball is a bump formed of a solder material having a relatively low melting point, and an alloy layer formed during a reflow process may be provided between the under bump metal layer 61 and the solder ball. For example, the solder ball may be made of Sn, Sn/Ag, Sn/Bi, Sn/Cu, Sn/Au, Sn/Ag/Cu, SnNiAgCu, SnNiAg, etc., but is not limited thereto.

The metal core ball is a double-structured bump including a metal core at the center and a solder buffer around the metal core. In this case, the metal core may be composed of Cu alone, a combination of Cu at the center and Ag at the outer side thereof, or may be composed of a triple combination including other metals outside of Ag. The solder buffer may include a solder material such as Pb or Sn having a relatively low melting point, and may be composed of an alloy of Ni or an alloy of Ag in addition to solder. The metal core ball may be formed by dropping a conductive ball according to a predetermined manual. In particular, since the metal core ball has a dual structure, the upper and lower packages are interconnected, such as the gas sensor package according to the sixth and seventh embodiments of the present invention. When used, the reliability of the entire package can be improved and gas inflow can be maintained more stably due to effects such as possible multi-reflow process, improvement of conductive properties, and stable maintenance of standoff. I can.

The plastic core ball is a double structured bump containing a central plastic core and a solder buffer around the plastic core. In this case, the plastic core may be composed of a combination of a plastic of a polymer material in the center and Ag of the outer side, or may be composed of a triple combination including other metals outside of the Ag. For example, as a polymer material, general general-purpose polymers such as PMMA (Polymethylmethacrylate), PS (Polystylene), PBO (Polybenzoxzaoles), acrylic polymers, imide polymers, arylether polymers, amide polymers, fluorine polymers, p-xyl It may include a rene-based polymer, a vinyl alcohol-based polymer, a polymer derivative having a phenolic group, and the like, but is not limited thereto. The solder buffer may include a solder material such as Pb or Sn having a relatively low melting point, and may be composed of an alloy of Ni or an alloy of Ag in addition to solder. In particular, since the plastic core ball has a dual structure, the upper and lower packages are interconnected, such as the gas sensor package according to the sixth and seventh embodiments of the present invention. When used, the reliability of the entire package can be improved and gas inflow can be maintained more stably due to effects such as possible multi-reflow process, improvement of conductive properties, and stable maintenance of standoff. I can.

The stud bump is a stud shaped bump. For example, the stud bump may be made of Au, Ag, Al, Cu, or the like, but is not limited thereto.

Further, referring to FIG. 6, the connection electrode 6 may include a Cu post 63.

The Cu post 63 is a conductive pillar having a certain height provided when a certain height is required for the gas sensor package, and may form a gap sufficient to allow the sensing layer 5 to be sufficiently exposed to gas. The Cu post 63 is provided to be exposed on the passivation layer 4, that is, the fourth passivation layer 44, which is the uppermost passivation layer 4, but is provided on the electrode pad 3, and is provided on the redistribution layer 2 It is electrically connected. Of course, the under bump metal layer 61 may also be provided, and in this case, a Cu post 63 is provided on the under bump metal layer 61.

In this case, when the Cu post 63 is included, the connection electrode 6 may further include a solder cap 64 provided on the Cu post 63 and electrically connected to the Cu post 63. In this case, the solder cap 64 is a solder material having a relatively low melting point, and may include a solder material such as Ag, Pb, or Sn, but is not limited thereto.

Hereinafter, a gas sensor package according to the second to seventh embodiments of the present invention will be described. However, the gas sensor package according to the second to seventh embodiments of the present invention has the same configuration as the gas sensor package according to the first embodiment except for some differences. Therefore, hereinafter, only these differences will be described.

4 is a cross-sectional view of a gas sensor package according to a second embodiment of the present invention mounted on a printed circuit board (PCB).

The gas sensor package according to the second embodiment of the present invention is a gas sensor package using a wafer level package process, and as shown in FIG. 4, except for the redistribution layer 2 and the passivation layer 4, the second embodiment of the present invention. It is the same as the configuration of the gas sensor package according to the first embodiment.

The passivation layer 4 further includes a fifth passivation layer 45.

The fifth passivation layer 45 is the uppermost passivation layer 4 and is stacked on the fourth passivation layer 44. In particular, the fifth passivation layer 45 has a groove, and the step 40 along with the groove of the fourth passivation layer 44 or the groove of the third passivation layer 43 and the fourth passivation layer 44 To form. In this case, the groove of the fifth passivation layer 45 may be formed to have a greater or equal width to the groove of the fourth passivation layer 44.

The redistribution layer 2 includes a first redistribution layer 21 and a second redistribution layer 22.

The first redistribution layer 21 is the same as the redistribution layer 2 included in the gas sensor package according to the first exemplary embodiment of the present invention, and the inside of the second passivation layer 42 to the third bashing layer 43 Can be provided in

The second redistribution layer 22 is a redistribution layer 2 added as the fifth passivation layer 45 is added, and provides a gap between the electrode pad 3 or the first redistribution layer 21 and the connection electrode 6. Connect electrically. In this case, the second redistribution layer 22 may be provided inside the fourth passivation layer 44 and the fifth passivation layer 45.

On the other hand, the electrode pad 3 is provided between the first redistribution layer 21 and the second redistribution layer 22 to electrically connect them, but the first redistribution layer 21 without the electrode pad 3 between them And the second redistribution layer 22 may be directly connected. Further, the electrode pad 3 may be provided between the second rewiring layer 22 and the connection electrode 6 to electrically connect them.

That is, the gas sensor package according to the second embodiment of the present invention has the fifth passivation layer 45, so that the area of the passivation layer 4 around the step portion 40 surrounding the sensing layer 5 is thicker. Therefore, the protection function of the sensing layer 5 can be further strengthened. Further, in the gas sensor package according to the second embodiment of the present invention, the position of the connection electrode 6 may be adjusted by adjusting the arrangement of the second redistribution layer 22.

5 is a cross-sectional view of a gas sensor package according to a third embodiment of the present invention mounted on a printed circuit board (PCB).

The gas sensor package according to the third embodiment of the present invention is a gas sensor package using a wafer level package process, except that the configurations of the through electrode 7 and the bump metal layer 8 are added as shown in FIG. 5. It is the same as the configuration of the gas sensor package according to the first embodiment of the present invention described above. That is, the gas sensor package according to the third embodiment of the present invention is a gas sensor package provided so that a plurality of gas sensor packages can be stacked on each other, as shown in FIG. 8.

The through electrode 7 is an electrode penetrating the semiconductor substrate 1 and is electrically connected to the redistribution layer 2.

The bump metal layer 8 is a configuration for improving the connection reliability of the bump 62 of the other gas sensor package when another gas sensor package is stacked on the gas sensor package to which it belongs, and plays the same role as the under bump metal layer 61. . In this case, the bump metal layer 8 is provided to be exposed under the semiconductor substrate 1 and is electrically connected to the through electrode 7. That is, the bump metal layer 8 provides a wetting layer to facilitate adhesion of the bumps 62 of other gas sensor packages and prevents penetration of the bumps 62 at the same time.

The bump metal layer 8 may be formed by a metallization method using a known metal, and various types of configurations are possible. For example, the bump metal layer 8 may be formed of Cu, Cu/Ni, Cu/Ni/Au, Cr/Cr-Cu/Cu, TiW/Cu, Al/NiV/Cu, etc., but is not limited thereto. .

Meanwhile, the gas sensor package according to the third embodiment of the present invention may further include an additional configuration of the gas sensor package according to the second embodiment of the present invention.

6 is a cross-sectional view of a gas sensor package according to a fourth embodiment of the present invention mounted on a printed circuit board (PCB).

The gas sensor package according to the fourth embodiment of the present invention is a gas sensor package using a wafer level package process, and as shown in FIG. 6, the contact electrode 6 comprises a Cu post 63 and a solder cap 64. Except for including, the configuration of the gas sensor package according to the first embodiment of the present invention is the same.

Since the Cu post 63 has already been described in the gas sensor package according to the first embodiment of the present invention, a description thereof will be omitted below.

Meanwhile, the gas sensor package according to the fourth embodiment of the present invention may further include an additional configuration of the gas sensor package according to the second or third embodiment of the present invention.

7 is a cross-sectional view of a gas sensor package according to a fifth embodiment of the present invention mounted on a printed circuit board (PCB).

The gas sensor package according to the fifth embodiment of the present invention is a gas sensor package using a wafer level package process, as shown in FIG. 7, except for including a plurality of gas sensor structures arranged side by side with each other. It is the same as the configuration of the gas sensor package according to the first embodiment of the invention.

That is, each gas sensor structure includes a redistribution layer 2, a metal pad 3, a passivation layer 4, a sensing layer 5, and a connection electrode 6, respectively, but to detect different types of gases. Another sensing layer 5 is included.

For example, the first gas sensor structure includes a redistribution layer (2 _HA ), a metal pad (3 _HA ), a passivation layer (4 _HA ), a sensing layer (5 _HA ), and a connection electrode (6 _HA ). In addition, the second gas sensor structure includes a redistribution layer 2 _HB , a metal pad 3 _HB , a passivation layer 4 _HB , a sensing layer 5 _HB , and a connection electrode 6 _HB . At this time, the first gas sensor structure and the second gas sensor structure are arranged side by side, and the detection layer 5 _{HA of} the first gas sensor structure and the detection layer 5 _HB of the second gas sensor structure are of different types. Can be made of a substance that reacts to the gas of

In particular, each gas sensor structure uses the semiconductor substrate 1 in common with each other. Of course, each gas sensor structure also uses the passivation layer 4 in common. However, the passivation layer 4 of each gas sensor structure includes separate step portions 40 from each other.

Meanwhile, the gas sensor package according to the fifth embodiment of the present invention may further include an additional configuration of the gas sensor package according to any one of the second to fourth embodiments of the present invention.

Since the gas sensor package according to the fifth embodiment of the present invention includes a plurality of gas sensor structures, it is possible to sense a plurality of gases.

8 is a cross-sectional view of a gas sensor package according to a sixth embodiment of the present invention mounted on a printed circuit board (PCB).

In the gas sensor package according to the sixth embodiment of the present invention, as shown in FIG. 8, except that gas sensor packages using a wafer level package process are stacked on each other, the gas sensor package according to the first embodiment of the present invention It is the same as the configuration of the gas sensor package.

That is, one gas sensor package according to the first embodiment of the present invention constitutes a gas sensor package, and a plurality of such gas sensor packages are stacked to form a gas sensor package according to the sixth embodiment of the present invention.

Each gas sensor package includes a semiconductor substrate (1), a redistribution layer (2), a metal pad (3), a passivation layer (4), a sensing layer (5), and a connection electrode (6), each of which contains different types of gases. It may include different sensing layers 5 to detect

For example, the first gas package includes a semiconductor substrate (1 _VA ), a redistribution layer (2 _VA ), an electrode pad (3 _VA ), a passivation layer (4 _VA ), a sensing layer (5 _VA ), and a connection electrode (6 _VA ). Each includes. In addition, the second gas package includes a semiconductor substrate (1 _VB ), a redistribution layer (2 _VB ), an electrode pad (3 _VB ), a passivation layer (4 _VB ), a sensing layer (5 _VB ), and a connection electrode (6 _VB ). Include. At this time, the first gas sensor package is disposed on the second gas sensor package, and the sensing layer 5 _{VA of} the first gas sensor package and the sensing layer 5 _VB of the second gas sensor package are of different types. May be made of a substance that reacts to gas

In particular, the first gas sensor package disposed at the top and the middle (when three or more gas sensor packages are stacked, referring to the rest except the bottom and the top) is made of the gas sensor package according to the third embodiment of the present invention. desirable. That is, the gas sensor package disposed at the top and the middle further includes a through electrode 7 _VA and a bump metal layer 8 _VA .

In this case, the through electrode 7 _VA of the first gas sensor package is electrically connected to the redistribution layer 2 _VA of the first gas sensor package. In addition, the through electrode 7 _VA of the first gas sensor package is electrically connected to the connection electrode 6 _VB of the second gas sensor structure through the bump metal layer 8 _VA of the first gas sensor structure.

Meanwhile, the first gas sensor package disposed at the top and the middle may further include an additional configuration of the gas sensor package according to the second embodiment of the present invention.

In addition, the second gas sensor package disposed on the lowermost portion may include a through electrode (7 _VB ) and a bump metal layer (8 _VB ), but without these configurations, any one of the first to fourth embodiments of the present invention It may be formed of a gas sensor package according to an embodiment.

The gas sensor package according to the sixth exemplary embodiment of the present invention includes a plurality of gas sensor packages, so that a plurality of gases can be sensed.

9 is a cross-sectional view of a gas sensor package according to a seventh embodiment of the present invention mounted on a printed circuit board (PCB).

In the gas sensor package according to the seventh embodiment of the present invention, gas sensor packages using a wafer level package process are stacked on each other, and as shown in FIG. 9, the contact electrode 6 comprises a Cu post 63. Except for including, the configuration of the gas sensor package according to the sixth embodiment of the present invention is the same.

Next, a gas sensor wafer level package according to an embodiment of the present invention will be described.

In the gas sensor wafer level package according to an embodiment of the present invention, as shown in FIG. 13, in the gas sensor package according to any one of the first to fifth embodiments of the present invention, the semiconductor substrate 1 It is the same except that) is replaced by the semiconductor wafer 10. That is, each of the gas sensor wafer level packages according to the first to fifth embodiments of the present invention corresponds to the gas sensor package according to the first to fifth embodiments of the present invention, but only the semiconductor substrate 1 It is replaced by a semiconductor wafer 10.

Meanwhile, the semiconductor wafer 10 includes a plurality of gas sensor packages that are not cut. That is, the semiconductor wafer 10 may include cut regions (indicated by dotted lines) between the gas sensor packages. For example, the semiconductor wafer 10 may be doped with n-type or p-type, and may be made of single crystal silicon or polycrystalline silicon, but is not limited thereto.

In the gas sensor package, the rewiring layer 2, electrode pad 3, passivation layer 4, sensing layer 5, connection electrode 6, through electrode 7 and the rest of the configurations excluding the semiconductor substrate 1 Since the bump metal layer 8 is the same as described above in the gas sensor package according to the first to fifth embodiments of the present invention, a description thereof will be omitted below.

Next, a method of manufacturing a gas sensor package according to various embodiments of the present disclosure will be described.

10 is a flowchart illustrating a method of manufacturing a gas sensor package according to an embodiment of the present invention. In addition, FIGS. 11 to 14 show S10 to S40 of a method for manufacturing a gas sensor package according to an embodiment of the present invention. In FIGS. 11 to 14, a dotted line indicates a cut area, that is, an area between each gas sensor package.

A method of manufacturing a gas sensor package according to an embodiment of the present invention includes a process of manufacturing each gas sensor package by cutting a plurality of gas sensor packages included in the gas sensor wafer package after forming the gas sensor wafer package. To this end, a method of manufacturing a gas sensor package according to an embodiment of the present invention includes S10 to S40, as shown in FIG. 10.

S10 is a preparation step, as shown in FIG. 11, to prepare the semiconductor wafer 10.

S20 is a step of forming a basic structure, and as shown in FIG. 12, a rewiring layer 2, an electrode pad 3, a passivation layer 4, and a connection electrode 6 which are basic structures on the semiconductor wafer 10 ) To form each. In this case, each of the redistribution layer 2, the electrode pad 3, the passivation layer 4, and the connection electrode 6 may be formed in this order, but is not limited thereto.

S30 is a step of forming the sensing layer 5, as shown in FIG. 13, to form a sensing layer 5 provided to be electrically connected to the redistribution layer 2 and exposed on the passivation layer 4.

Since S30 is performed after S20, the manufacturing method of the gas sensor package according to an embodiment of the present invention has an advantage of preventing damage to the sensing layer 5 that may occur during S20. As such, it is possible to perform S30 after S20 according to the structural characteristics of the gas sensor package according to an embodiment of the present invention in which the sensing layer 5 is provided within the step 40 of the passivation layer 4. This is an advantage.

S40 is a cutting step, and as shown in FIG. 14, each gas sensor package is cut along the cut area. At this time, each of the cut gas sensor packages includes a semiconductor substrate 1, a redistribution layer 2, an electrode pad 3, a passivation layer 4, a sensing layer 5, and a connection electrode 6, respectively.

When performing S10 to S40, the gas sensor package according to the first to fourth embodiments of the present invention described above may be manufactured. At this time, the configurations of the semiconductor substrate 1, the redistribution layer 2, the electrode pad 3, the passivation layer 4, and the connection electrode 6 are as described above in the gas sensor package and the gas sensor wafer package. Description of these will be omitted.

However, in order to strengthen the protection function of the sensing layer 5, S20 may include forming a passivation layer 4 having a stepped portion 40 having a stepped shape, and S30 is within the stepped portion 40. It may include the step of forming the sensing layer (5). In this case, S20 is a step of forming a step 40 between the connection electrodes 6, but forming each connection electrode 6 on the passivation layer 4 region around the step 40 other than the step 40 It may include.

On the other hand, in the case of manufacturing the gas sensor package according to the fifth embodiment of the present invention, S30 includes forming a plurality of different sensing layers 5 in regions of each gas sensor package. In addition, S40 is a step of cutting each gas sensor package such that a plurality of gas sensor structures that are arranged in parallel with each other and have different sensing layers 5 but use a common semiconductor substrate 1 are included in each gas sensor package. Includes. At this time, each gas sensor structure includes a common semiconductor substrate 1, a redistribution layer 2, an electrode pad 3, a passivation layer 4, a sensing layer 5, and a connection electrode 6, respectively.

In addition, in the case of manufacturing a package in a POP (Package on Package) type, that is, a gas sensor package according to the sixth or seventh exemplary embodiment of the present invention, manufacturing a gas sensor package according to an exemplary embodiment of the present invention. The method further includes a lamination step performed after S40.

That is, the laminating step is a step of laminating a plurality of gas sensor packages cut by S40 to each other. At this time, it is preferable that each stacked gas sensor package includes a different sensing layer 5.

In particular, in order to stack each gas package according to the stacking step, it is preferable that the gas sensor package disposed at the top and the middle is formed of the gas sensor package according to the third embodiment of the present invention. That is, S20 includes a step of further forming a through electrode 7 _VA and a bump metal layer 8 _VA for the gas sensor package disposed at the top and the middle. Accordingly, in the laminating step, the through electrode 7 _VA of the first gas sensor package provided on the second gas sensor package is passed through the bump metal layer 8 _VA of the second gas sensor structure. Further comprising the step of electrically connecting to the connection electrode (6 _VB ).

In the detailed description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the present invention is not limited to the described embodiments, and should be determined by the scope of the claims to be described later and those equivalent to the scope of the claims.

1: semiconductor substrate 2, 21, 22: redistribution layer
3: electrode pads 4, 41, 42, 43, 44, 45: passivation layer
5: sensing layer 6: connection electrode
7: through electrode 8: bump metal layer
10: semiconductor wafer 40: step portion
61: under bump metal layer 62: bump
63: Cu post 64: solder cap

Claims (14)

As a gas sensor package,
A semiconductor substrate;
A redistribution layer provided on the semiconductor substrate and electrically connected to the sensing layer to transmit a gas sensing signal;
A passivation layer provided to cover the redistribution layer and having a stepped portion formed in a stepped shape;
A sensing layer provided to be exposed on the passivation layer to detect gas, but provided in the stepped portion; And
And a plurality of connection electrodes electrically connected to the redistribution layer and exposed on the passivation layer so as to be connected to external terminals and connectable to a printed circuit board (PCB), and
The gas sensor package, characterized in that the step portion is provided between the connection electrodes. delete delete The method of claim 1,
The connection electrode,
An under bump metal layer electrically connected to the redistribution layer and exposed on the passivation layer; And
A gas sensor package comprising: a bump electrically connected to the under bump metal layer and provided on the under bump metal layer. The method of claim 1,
The connection electrode,
A Cu post electrically connected to the redistribution layer and exposed on the passivation layer and having a predetermined height; And
A gas sensor package comprising: a solder cap electrically connected to the Cu post and provided on the Cu post. The method of claim 1,
Each of the semiconductor substrate, the redistribution layer, the passivation layer, the sensing layer, and the connection electrode, but having different sensing layers and including a plurality of gas sensor packages arranged to be stacked on each other,
The first gas sensor package stacked on the second gas sensor package further includes a through electrode penetrating its own semiconductor substrate and electrically connected to its own redistribution layer and a connection electrode of the second gas sensor structure. Gas sensor package. The method of claim 1,
Each of the redistribution layer, the passivation layer, the sensing layer, and the connection electrode includes a plurality of gas sensor structures having different sensing layers and arranged in parallel with each other,
Each gas sensor structure includes the semiconductor substrate that is used in common with each other. Semiconductor wafers;
A redistribution layer provided on the semiconductor wafer and electrically connected to the sensing layer to transmit a gas sensing signal;
A passivation layer provided to cover the redistribution layer and having a stepped portion formed in a stepped shape;
A sensing layer provided to be exposed on the passivation layer to detect gas, but provided in the stepped portion; And
And a plurality of connection electrodes electrically connected to the redistribution layer and exposed on the passivation layer so as to be connected to external terminals and connectable to a printed circuit board (PCB), and
The gas sensor wafer level package, wherein the step portion is provided between the connection electrodes. (a) preparing a semiconductor wafer;
(b) A redistribution layer provided on a semiconductor wafer to transmit a gas detection signal, a passivation layer provided to cover the redistribution layer and having a stepped portion formed in a stepped shape, and electrically connected to the redistribution layer, so that connection with external terminals is possible. Forming a plurality of connection electrodes provided to be exposed on the passivation layer and connectable to a printed circuit board (PCB);
(c) sensing a gas electrically connected to the redistribution layer and provided to be exposed on the passivation layer, but forming a sensing layer provided in the step portion; And
(d) cutting each gas sensor package including a semiconductor substrate, a redistribution layer, a passivation layer, a sensing layer, and a connection electrode; includes,
The method of manufacturing a gas sensor package, wherein the step portion is provided between the connection electrodes. delete delete The method of claim 9,
(e) a method of manufacturing a gas sensor package, further comprising stacking a plurality of gas sensor packages having different sensing layers on each other. The method of claim 12,
The step (b) further includes forming a through electrode penetrating the semiconductor substrate and electrically connected to the redistribution layer,
The step (e) further comprises electrically connecting the through electrode of the first gas sensor package stacked on the second gas sensor package to the connection electrode of the second gas sensor package. Manufacturing method. The method of claim 9,
The step (c) includes forming a plurality of different sensing layers within the region of each gas sensor package,
The step (d) includes cutting each gas sensor package such that a plurality of gas sensor structures arranged in parallel with each other and having different sensing layers but using a common semiconductor substrate are included in each gas sensor package,
Each of the gas sensor structures includes a common semiconductor base, a redistribution layer, a passivation layer, a sensing layer, and a connection electrode.

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