KR101118223B1 - Bio-sensor for measuring magnetoresistive and method for manufacturing the same - Google Patents

Abstract

The present invention relates to a magnetoresistive measurement biosensor based on reverse structure substrate etching and a method of manufacturing the same. In the biosensor of the present invention, the dielectric layer is first formed, and then the magnetoresistance sensor is formed, so that the dielectric layer can be formed at a high temperature without damaging the stability of the magnetoresistance sensor. Therefore, the biosensor of the present invention includes a high quality dielectric layer thin film and has excellent measurement sensitivity accordingly. In addition, since the sample application container is formed on the sample contact metal film by etching the substrate without a separate process, the application of the sample is very convenient.

Magnetoresistive sensor, biosensor, dielectric layer, substrate etching

Description

Biosensor measuring magnetoresistance and its manufacturing method {BIO-SENSOR FOR MEASURING MAGNETORESISTIVE AND METHOD FOR MANUFACTURING THE SAME}

The present invention relates to a magnetoresistive measurement biosensor and a method for manufacturing the same, and more particularly, to a magnetoresistance measurement biosensor based on inverse structure substrate etching and a method for manufacturing the same.

The present invention is derived from a study conducted as part of the IT original technology development project of the Ministry of Knowledge Economy and the Ministry of Information and Communication Research and Development. [Task management number: 2006-S-074-03, Title: High-performance biosensor system using nanoparticles ].

In general, the magnetoresistive biosensors used to read biomaterials such as DNA may include a magnetoresistive sensor 12, an electrode 14, and a dielectric layer 16 sequentially from the substrate 10 as illustrated in FIGS. 1 to 3. , The adhesion-improving metal film 18 and the sample contact metal film 20 are laminated.

However, the magnetoresistance measurement biosensor formed as described above has a low thermal stability of the magnetoresistance sensor 12 at 180 ° C. or lower, so that a high temperature process such as low-pressure chemical vapor deposition (LPCVD) is used to form the dielectric layer 16. It is impossible to apply. Therefore, the process of forming the dielectric layer 16 must be performed at a low temperature. In this case, a problem occurs in that a dielectric layer having a low density and many defects is formed. In addition, in order to overcome this problem, a method of forming a thick dielectric layer may be considered. In the case of forming a thick dielectric layer, the measurement sensitivity of the biosensor decreases significantly (from the magnetoresistive sensor 12). Decrease in measurement sensitivity in inverse proportion to the cube root of the distance between particles). Therefore, securing the quality of the dielectric layer 16 in the magnetoresistive measurement biosensor is recognized as a problem to be solved to improve the quality of the biosensor.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems of the prior art, and has a magnetoresistance measurement bio which forms a dielectric layer at a high temperature of 180 ° C. or higher without damaging the stability of the magnetoresistance sensor included in the magnetoresistance measurement biosensor. It is an object to provide a method for manufacturing a sensor.

In addition, by the above-described manufacturing method, by including a high-quality dielectric layer thin film exhibits excellent measurement sensitivity, a sample application container is formed on the sample contact metal film without a separate process to provide a very convenient biosensor For the purpose of

The present invention,

(a) sequentially depositing a sample contact metal film, a dielectric layer, a magnetoresistive sensor and an electrode on the substrate; And

(b) providing a method of manufacturing a magnetoresistive measurement biosensor comprising etching the substrate from below so that the sample contact metal film is exposed.

In addition,

A sample contact metal film, a dielectric layer, a magnetoresistance sensor, and an electrode are sequentially stacked on the substrate, and the substrate may be exposed from the bottom of the substrate so that an unetched portion may serve as a sample application container. It provides a magnetoresistance measurement biosensor characterized in that it has an etched shape until.

According to the manufacturing method of the biosensor for measuring magnetoresistance of the present invention, by forming the dielectric layer first and then forming the magnetoresistance sensor, the dielectric layer can be formed at a high temperature of 180 ° C. or higher without damaging the stability of the magnetoresistance sensor. Therefore, the magnetoresistive measurement biosensor manufactured by the manufacturing method of the present invention includes a high quality dielectric layer thin film and has excellent measurement sensitivity accordingly.

In addition, according to the manufacturing method of the present invention, since the sample application container is formed on the sample contact metal film by etching the substrate without a separate process, it is possible to provide a biosensor which is very convenient to apply the sample.

The present invention,

(a) sequentially depositing a sample contact metal film, a dielectric layer, a magnetoresistive sensor and an electrode on the substrate; And

and (b) etching the substrate from below to expose the sample contact metal film.

Since the magnetoresistive sensor is formed after the dielectric layer is formed as described above, the manufacturing method of the present invention does not affect the stability of the magnetoresistive sensor at all. Therefore, according to the present invention, it is possible to form a dielectric layer at a high temperature, thereby improving the quality of the dielectric layer.

The step (a) may further include a step of forming a protective layer for protecting the magnetoresistive sensor and the electrode after the electrode is laminated.

In addition, the step (a) may further include a step of forming a metal film for improving adhesion between at least one of the substrate and the sample contact metal film and between the sample contact metal film and the dielectric layer.

In the step (b), the etching of the substrate may be performed at the bottom of the substrate until the non-etched portion may serve as a sample application container and until the sample contact metal film is exposed, and the etching may be performed on the etching solution before etching. The non-melting resist layer may be laminated on the lower surface of the substrate, and selectively removed the stacked resist to be etched, followed by wet etching.

In the present invention, the sample application container means a structure that blocks the flow of the sample by forming a boundary with a periphery to prevent the sample from flowing down from the sample contact metal film.

As described above, when the sample application container is formed together with the etching of the substrate, application of the sample is very convenient, and it is very economical because it is not necessary to form the sample application container by a separate process.

In addition,

The sample contact metal film, the dielectric layer, the magnetoresistance sensor and the electrode are sequentially stacked on the substrate, and the substrate is exposed when the sample contact metal film is exposed from the bottom of the substrate so that the unetched portion can serve as a sample application container. It relates to a magnetoresistive measurement biosensor, characterized in that it has an etched form.

In the present invention, the sequential means the up and down relationship of the stacking position of each stacking portion, and does not necessarily mean that each stacking portion is formed by direct contact. Therefore, the case where another laminated part is inserted between the laminated parts described above also falls within the scope of the present invention.

The biosensor of the present invention may further include a protective layer laminated to protect the magnetoresistive sensor and the electrode.

The present invention may further include a metal film for improving adhesion, which is laminated between at least one of the substrate and the sample contact metal film and between the sample contact metal film and the dielectric layer.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention. Prior to describing the present invention, if it is determined that a detailed description of related known functions and configurations may unnecessarily obscure the subject matter of the present invention, the description thereof will be omitted.

4 (a) to (j) is a process diagram sequentially showing the manufacturing process of the magnetoresistance measurement biosensor as an embodiment of the present invention, Figure 5 is a magnetoresistance measurement biosensor manufactured by the process of FIG. Indicates.

First, the magnetoresistive measurement biosensor 200 illustrated in FIG. 4 will be described. As shown in FIGS. 4A to 4D, the metal film 110 for improving adhesion may be formed on the substrate 100. The sample contact metal film 120 is laminated on the adhesive force improving metal film 110, and the metal layer 110 for improving adhesion is laminated on the sample contact metal film 120. As the substrate 100, a high resistance (resistance 1> Mohm-cm) silicon (directional 100) substrate may be used, and the Ti (<10 nm) thin film may be deposited as the metal film 110 for improving adhesion. In addition, an Au (<200 nm) thin film may be deposited on the sample contact metal film 120. Each of the adhesion-improving metal layers 110 may be deposited with the same metal or different metals.

Next, as shown in FIG. 4E, the dielectric layer 130 is formed on the adhesion force improving metal film 110. A thin film, such as Si ₃ N ₄ , may be deposited as the dielectric layer, and may be formed to a thickness of 100 to 300 nm by a process such as LPCVD. In this case, when wet etching the substrate 100, the resist layer 140 necessary for etching only a desired portion may also be formed under the substrate. Since the material of the resist layer may be one that does not dissolve in an etchant, the resist layer may be laminated using the same material as that of the dielectric layer.

Next, as shown in FIGS. 4F and 4G, the magnetoresistive sensor 150 is stacked on the dielectric layer 130, and the electrode 160 is stacked.

Next, the sample contact metal film 120 is processed and wired by using lift-off on the magnetoresistive sensor 150 and the electrode 160 (not shown).

Next, as shown in FIG. 4H, a protective layer 170 for protecting the magnetoresistive sensor 150 and the electrode 160 is formed on the wiring of the sample contact metal film 120. As the protective layer, a material such as UV curing epoxy may be used.

Next, as shown in (i) and (j) of FIG. 4, an etching pattern of the substrate 100 is formed on the resist layer 140 by a lithography process or a dry etching process (RIE, ion-milling). . Next, the substrate 100 is etched with a wet etchant until the substrate is completely penetrated. As the etchant, KOH (eg, KOH concentration of 10 to 40 wt%, aqueous solution temperature of 60 to 90 ° C.), or the like may be used. In the etching process, the etching angle is maintained at 54.74¡Æ until the substrate is completely penetrated. At this time, the adhesion-improving metal film 110 is removed using an appropriate etching solution.

The substrate etching process may be performed by a dry etching process without forming the resist layer 140.

5 illustrates a magnetoresistive measurement biosensor manufactured by the above process. As shown in FIG. 5, a biological sample such as an oligonucleotide is fixed and used on the surface of the sample contact metal film 120 in the sample application container 180.

Although the present invention has been described in connection with the above-mentioned preferred embodiment,

Various modifications and variations can be made without departing from the spirit and scope of the invention.

Do. Accordingly, the appended claims will cover such modifications and variations as long as they fall within the spirit of the invention.

1 is a view showing a laminated structure of a conventional magnetoresistance measurement biosensor.

2 to 3 briefly illustrate a method of detecting a biomaterial using a conventional magnetoresistive measurement biosensor.

4 is a view briefly illustrating a manufacturing process of the magnetoresistive measuring biosensor according to an embodiment of the present invention.

5 is a cross-sectional view of a magnetoresistive measurement biosensor according to the present invention.

* Description of Drawing Symbols *

100: substrate 110: metal film for improving adhesion

120: sample contact metal film 130: dielectric layer

140: resist layer 150: magnetoresistance sensor

160: electrode 170: protective layer

180: sample application container 200: magnetoresistance measurement biosensor

Claims (8)

(a) sequentially depositing a sample contact metal film, a dielectric layer, a magnetoresistive sensor and an electrode on the substrate; And (b) etching the substrate from below so that the sample contact metal film is exposed.  The method of claim 1, wherein the step (a) further includes forming a magnetoresistive sensor and a protective layer for protecting the electrode after the electrode is stacked.  The magnetoresistance measurement according to claim 1, wherein the step (a) further comprises forming a metal film for improving adhesion between at least one of the substrate and the sample contact metal film and between the sample contact metal film and the dielectric layer. Method of manufacturing a biosensor.  The method of claim 1, wherein in step (b), the etching of the substrate is performed at the bottom of the substrate so that the unetched portion can serve as a sample application container, and is performed until the sample contact metal film is exposed. Method of manufacturing a resistance sensor biosensor.  The method of claim 4, wherein in the step (b), the substrate is etched by laminating a resist layer which is insoluble in the etchant prior to etching on the lower surface of the substrate, and selectively removing the stacked resist to be etched, followed by wet etching. Method of manufacturing a magnetoresistance measurement biosensor, characterized in that. A sample contact metal film, a dielectric layer, a magnetoresistance sensor, and an electrode are sequentially stacked on the substrate, and the substrate may be exposed from the bottom of the substrate so that the unetched portion may serve as a sample application container. Magnetoresistance measurement biosensor characterized in that it has an etched shape until.  The magnetoresistance measurement biosensor of claim 6, wherein the magnetoresistance measurement biosensor further comprises a protective layer laminated to protect the magnetoresistance sensor and the electrode.  7. The magnetoresistance measurement according to claim 6, wherein the magnetoresistance measurement biosensor further comprises a metal film for improving adhesion, which is laminated between at least one of the substrate and the sample contact metal film and between the sample contact metal film and the dielectric layer. Biosensor.

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