JP2006120942A - Resistance element and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of a resistance element which exhibits a high resistance characteristic even though being positioned under a heating environment and can be formed small in size and preciously, and to provide the resistance element. <P>SOLUTION: The method for manufacturing the resistance element, which has an element electrode and a resistance layer, includes (a) an electroless plating process which forms the resistance layer on a substrate by an electroless plating method using an electroless plating nickel/phosphorous liquid containing a complexing agent, which is of a nickel salt, a reducing agent, and an amino-group-contained compound(where, the amino-group is -NH<SB>2</SB>and/or >NH); (b) an acid treatment process which performs an acid treatment on the resistance layer. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a resistance element manufacturing method and a resistance element.

In recent years, as devices such as mobile phones and digital cameras have become smaller and lighter, it is difficult for conventional devices to be mounted on printed wiring boards using conventional mounting technologies such as reducing the size of devices and reducing the distance between devices. Therefore, there is an increasing expectation for a printed wiring board incorporating these elements. In order to prevent the substrate containing the element from becoming thick, there is an urgent need to develop a method capable of sufficiently satisfying characteristics with a thin component or a film element.
As a method of forming a resistance element on a printed wiring board, a method of forming a resistance layer with a metal thin film on a copper foil, a method of forming a resistance layer on a substrate by electroless plating, or printing a resistive thick film polymer There are methods. It is necessary to select a forming method according to the application from the resistance value, accuracy, shape, price, and the like. In the method of printing a thick film polymer, it is possible to form a high-resistance material, but it is difficult to form a fine size. The thin film type using a metal material is restricted to a low resistance range as compared with the thick film type, but can be formed with a small size and high accuracy.
As a method for forming a resistance element with a metal thin film on a copper foil, there is Ohmega-Ply of Ohmega Technologies, USA. In this method, a thin film resistance layer formed by electrolytic nickel / phosphorous plating on a copper foil is laminated on a substrate, and each is formed into a resistance element by using a resistance element electrode and a resistance film (for example, Patent Document 1). reference).
As a method for forming a resistance element on a substrate by plating, there is M-Pass of Macermid, USA. In this method, after forming a wiring pattern in which a part of the wiring is separated on the substrate, a resistance layer is formed by electroless nickel / phosphorous plating between the partially separated wirings to form a resistance element. (For example, refer to Patent Document 2).
US Pat. No. 4,808,967 JP-A-10-190183

  However, it is difficult to maintain high electrical resistance characteristics (sheet resistance value, etc.) even when placed in a heating environment in a resistance element made of a nickel / phosphorus thin film formed by conventional electroless plating. . For this reason, it is desired to develop a resistance element that exhibits stable electrical resistance characteristics even in various applications placed in a heating environment and can be formed with high accuracy in a small size.

  The present invention has been made in view of the above circumstances, and can provide a resistance element that exhibits high electrical resistance characteristics even when placed in a heating environment and that can be formed with high accuracy in a small size. It is an object to provide a method and a resistance element.

In order to solve the above problems, an invention according to claim 1 is a method of manufacturing a resistance element including an element electrode and a resistance layer.
(A) Electroless plating method using an electroless nickel / phosphorous plating solution containing a complexing agent which is a nickel salt, a reducing agent and an amino group-containing compound (wherein the amino group is —NH ₂ and / or> NH) An electroless plating process for forming a resistance layer on the substrate by
(B) an acid treatment step of subjecting the resistance layer to an acid treatment;
A method of manufacturing a resistance element.

  The invention according to claim 2 is characterized in that after the acid treatment step (b), (c) a heat treatment step of heat-treating the resistance layer is performed. It is.

  The invention according to claim 3 is the method of manufacturing a resistance element according to claim 2, wherein the heat treatment (c) is performed within a range of 100 to 850 ° C.

  The invention according to claim 4 is the method of manufacturing a resistance element according to any one of claims 1 to 3, wherein the resistance layer has a sheet resistance value at 200 ° C. of 20Ω / □ or more.

The invention according to claim 5 is a method of manufacturing a resistance element including an element electrode and a resistance layer.
(A-1) forming a resistance layer on the entire surface of the substrate by plating;
(B-1) forming a wiring pattern comprising the resistance layer and the conductor layer after forming a conductor layer on the substrate;
(C-1) etching a predetermined portion of the conductor layer to expose a resistance layer under the conductor layer;
Comprising the step of forming the resistance layer,
(A) Electroless plating method using an electroless nickel / phosphorous plating solution containing a complexing agent which is a nickel salt, a reducing agent and an amino group-containing compound (wherein the amino group is —NH ₂ and / or> NH) An electroless plating process for forming a resistance layer on the substrate by
(B) an acid treatment step of subjecting the resistance layer to an acid treatment;
A method of manufacturing a resistance element.

  The invention according to claim 6 is characterized in that, after the acid treatment step (b), (c) a heat treatment step of heat-treating the resistance layer is performed. It is.

The invention according to claim 7 is a method of manufacturing a resistance element including an element electrode and a resistance layer.
(A-2) forming a patterned resistance layer on the substrate;
(B-2) forming a conductor layer on the substrate;
Comprising the step of forming the resistance layer,
(A) Electroless plating method using an electroless nickel / phosphorous plating solution containing a complexing agent which is a nickel salt, a reducing agent and an amino group-containing compound (wherein the amino group is —NH ₂ and / or> NH) An electroless plating process for forming a resistance layer on the substrate by
(B) an acid treatment step of subjecting the resistance layer to an acid treatment;
A method of manufacturing a resistance element.

  The invention according to claim 8 is characterized in that, after the acid treatment step (b), (c) a heat treatment step of heat-treating the resistance layer is performed. It is.

The invention according to claim 9 is a method of manufacturing a resistance element including an element electrode and a resistance layer.
(A) Electroless plating method using an electroless nickel / phosphorous plating solution containing a complexing agent which is a nickel salt, a reducing agent and an amino group-containing compound (wherein the amino group is —NH ₂ and / or> NH) An electroless plating process for forming a resistance layer on the substrate by
(B) an acid treatment step of subjecting the resistance layer to an acid treatment;
It is a resistance element formed by the process which comprises.

According to the present invention, an electroless nickel / phosphorous plating solution containing a complexing agent that is a nickel salt, a reducing agent, and an amino group-containing compound (wherein the amino group is —NH ₂ and / or> NH) is used. Because it is a resistive element with a resistance layer made of an acid-treated nickel-phosphorus thin film formed by electroplating, it was formed by conventional electroless plating, even without chromium eutectoid It has much higher electric resistance characteristics than nickel-phosphorus thin films, and can prevent deterioration of electric resistance characteristics due to heat.
Furthermore, by subjecting the resistance layer to heat treatment, the thermal stability of the electrical resistance characteristics of the resistance layer is improved, and stable electrical resistance characteristics can be expressed even in various applications placed in a heating environment.

  The resistance element manufacturing method of the present invention comprises forming a resistance layer on a substrate by an electroless plating method using an electroless nickel / phosphorous plating solution containing a nickel salt, a reducing agent, and a complexing agent which is an amino group-containing compound. After film (a), acid treatment (b) and heat treatment (c) as necessary are performed, and a resistance element having a sheet resistance value of 20 Ω / □ or more at 200 ° C. can be produced. .

  The substrate for forming the resistance element of the present invention is not particularly limited, and can be used from various synthetic resin plates, flexible sheets, glass plates, ceramic plates, and metal substrates having an insulating layer on the surface. It can be appropriately selected and used according to the above. A wiring circuit or other passive element may be formed in advance in the inner layer.

Examples of the complexing agent that is an amino group-containing compound constituting the electroless nickel / phosphorous plating solution include α-alanine, β-alanine, diethylenetriamine, L-glutamate, glycine, triethylenetetramine, and tetraethylenepentamine. And amino acids containing an amino group (—NH ₂ ,> NH) such as monoethanolamine and diethanolamine, and amines. In particular, an amino group-containing compound selected from the group consisting of α-alanine, β-alanine, diethylenetriamine, L-glutamate and glycine is preferably used as the complexing agent.
The concentration of such a complexing agent in the plating solution can be about 0.1 to 2.0 mol / L, preferably about 0.5 to 1.5 mol / L. When the concentration of the complexing agent is less than 0.1 mol / L, the bath stability is lowered, and when it exceeds 2.0 mol / L, the deposition rate is undesirably slowed. The ratio of the complexing agent and nickel concentration (mol / L) in the plating solution is preferably in the range of 1: 1 to 20: 1. When the ratio of the complexing agent is less than the above range, the sheet resistance of the formed nickel / phosphorus thin film becomes insufficient, which is not preferable.

  Nickel sulfate, nickel chloride, nickel hypophosphite, nickel carbonate, etc. can be used as the nickel salt constituting the nickel / phosphorous plating solution used in the present invention. The concentration of the nickel salt in the plating solution can be about 0.01 to 1.0 mol / L, preferably about 0.05 to 0.2 mol / L. When the concentration of the nickel salt is less than 0.01 mol / L, the deposition rate is slow, and when it exceeds 1.0 mol / L, the bath stability is undesirably lowered.

  As the reducing agent constituting the nickel / phosphorous plating solution used in the present invention, sodium hypophosphite, dimethylboraneamine, hydrazine and the like can be used. The concentration of the reducing agent in the plating solution can be about 0.05 to 1.0 mol / L, preferably about 0.1 to 0.3 mol / L. When the concentration of the reducing agent is less than 0.05 mol / L, the deposition rate is slow, and when it exceeds 1.0 mol / L, the bath stability is undesirably lowered.

Formation of the nickel / phosphorus thin film by the electroless plating method using the above electroless nickel / phosphorous plating solution can be performed, for example, under conditions of a bath temperature of 60 to 90 ° C. and a bath pH of 4 to 7. If the bath temperature is less than 60 ° C, the deposition temperature is slow, and if it exceeds 90 ° C, the bath stability is lowered, which is not preferable. On the other hand, if the bath pH is out of the above range, the film formation rate and the sheet resistance become insufficient, which is not preferable.
The nickel / phosphorous thin film formed by the electroless plating method using the above electroless nickel / phosphorous plating solution is nickel formed by the conventional electroless plating method even though it does not involve chromium eutectoid. -It has a much higher electric resistance characteristic than a phosphorus thin film.

The resistance element of the present invention further improves the electric resistance characteristics of the resistance layer by applying acid treatment and heat treatment to the resistance layer formed using the above electroless nickel / phosphorous plating solution, and is also thermally stable. This prevents the deterioration of electrical resistance characteristics due to heat. Although the mechanism of thermal stabilization of the electrical resistance characteristics by the above treatment is unknown, the resistance treatment having a sheet resistance value of 20Ω / □ or more at 200 ° C. can be obtained by acid treatment as well as after acid treatment. For this reason, the resistance element of the present invention can exhibit stable electric resistance characteristics even when used in various applications placed in a heating environment.
In the present invention, the sheet resistance value at 200 ° C. of the resistance layer means that the resistance layer is left in an atmosphere of 200 ° C. for 30 minutes, and then the four-end needle method (Loresta MPMCP-T350 manufactured by Mitsubishi Chemical Corporation) is used. Means measured.

  Acids used for acid treatment include nitric acid, sulfuric acid, boric acid, carbonic acid, nitrous acid, silicic acid, borosilicate, phosphoric acid, phosphorous acid, hypophosphorous acid, sulfurous acid, persulfuric acid, hydrogen sulfide water, and fluoride. Hydrochloric acid, borohydrofluoric acid, hydrochloric acid, chlorous acid, hypochlorous acid, perchloric acid, hydrobromic acid, hypobromite, bromic acid, hydroiodic acid, hypoiodous acid, iodic acid, etc. Inorganic acids: formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, heptyl acid, caprylic acid, pelargonic acid, capric acid, undecyl acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, acrylic acid , Crotonic acid, oleic acid, linoleic acid, linolenic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, capric acid, arachidic acid, wax Sen acid, erucic acid, Richinoru acid, fumaric acid, maleic acid, lactic acid, malic acid, tartaric acid, and organic acids such as citric acid. As the acid treatment method, immersion in an acid aqueous solution, spraying of an acid aqueous solution, or the like can be used. The concentration of the acid aqueous solution (for example, nitrate concentration, sulfate concentration) can be set in the range of 1 to 900 g / L, and the temperature of the acid aqueous solution can be set in the range of 0 to 100 ° C. In the case of acid treatment by immersion, the acid aqueous solution may be stirred. By performing the acid treatment in this way, the sheet resistance value of the resistance layer after the acid treatment is increased as compared with the sheet resistance immediately after the electroless plating. The acid treatment step is preferably performed by immersing the substrate in a nitric acid solution.

  The resistance element of the present invention also has an effect of further increasing the sheet resistance value by performing heat treatment depending on the type of complexing agent constituting the electroless nickel / phosphorous plating solution. For example, when diethylenediamine is used as the complexing agent, the sheet resistance value is remarkably increased by performing the heat treatment after the acid treatment. On the other hand, when L-glutamate is used as the complexing agent, the sheet resistance value is stable even when heat treatment is performed. Therefore, the resistance element of the present invention can arbitrarily set the sheet resistance value provided after the heat treatment by appropriately selecting the complexing agent used in the electroless nickel / phosphorous plating solution. Said heat processing can be performed within the range of 100-850 degreeC, for example.

  Next, a method for incorporating the resistance element of the present invention in a printed wiring board will be described. In order to incorporate the resistance element of the present invention in a printed wiring board, a resistance layer formed in a predetermined resistance element formation region and two conductor layers in contact with the resistance layer are formed. The two conductor layers are separated from each other and can be used as an element electrode of a resistance element. As a material for the conductor layer, a metal material having good conductivity such as gold, silver, copper, nickel, and aluminum is preferable.

Hereinafter, a method for forming a resistance element on a substrate will be described as an example. Here, the following areas are set on the substrate for convenience of explanation.
Region where the resistance layer is formed in a state where the resistance element is completed: a resistance element forming region,
Area where conductor layer to be element electrode is formed ... Element electrode formation area,
A region where the resistance layer is exposed to separate the two conductor layers .... A device electrode separation region.

A first method for incorporating the resistance element in the printed wiring board includes the following steps (A-1) to (C-1) (see FIG. 1).
(A-1) A step of forming the resistance layer 2 on the entire surface of the substrate 1 by plating [see FIG.
(B-1) A step of forming a wiring pattern 4 composed of the resistance layer 2 and the conductor layer 3 after forming the conductor layer 3 on the substrate 1 [see FIG. 1 (b) to FIG. 1 (d)].
(C-1) A step of etching a predetermined portion of the conductor layer 3 to expose the resistance layer 2 under the conductor layer 3 [see FIG. 1 (e) to FIG. 1 (f)].

Here, the step (A-1) is performed as an electroless plating step (a) for forming a nickel / phosphorus thin film to be the resistance layer 2 using the above-described electroless nickel / phosphorous plating solution.
The acid treatment step (b) can be performed at any stage as long as the resistance layer 2 is exposed as long as the acid used for the acid treatment does not affect the conductor layer 3. 1) may be performed between step (B-1), may be performed between step (B-1) and step (C-1), or may be performed after step (C-1). Also good. If the acid treatment step (b) is performed between the step (A-1) and the step (B-1), the conductor layer 3 is not formed at this stage, so the acid treatment is performed regardless of the material of the conductor layer 3. The acid to be used can be freely selected and is preferred. If it is performed between the stage shown in FIG. 1A and the stage shown in FIG. 1B, the entire surface of the resistance layer 2 is exposed, so that the treatment can be performed uniformly and the conductive layer 3 can be formed. It is most preferable because it is not necessary to consider the influence of
The acid treatment step is preferably performed before the trimming step because trimming can be performed with a stable resistance value.
When the heat treatment step (c) is performed, it may be performed at any stage after the acid treatment step (b), or may be performed between the step (A-1) and the step (B-1). And you may carry out between a process (B-1) and a process (C-1), and may carry out after a process (C-1). When trimming is performed, it is preferable to perform the heat treatment step (c) before the trimming step in order to suppress the influence of heat generated during trimming.

In the step (B-1), the wiring pattern 4 in which the resistance layer 2 and the conductor layer 3 are laminated is formed in the resistance element formation region 5. The resistance element forming region 5 is set in an appropriate shape such as a rectangle or a meander structure so that a desired resistance value can be obtained. After the step (B-1) is completed, the resistance layer 2 and the conductor layer 3 are removed and the substrate 1 is exposed outside the resistance element formation region 5 [see FIG. 1 (d)].
Step (B-1) can be performed, for example, by sequentially performing the following procedures (1) to (3).
(1) The conductor layer 3 is formed on the entire surface of the resistance layer 2 [see FIG. 1 (b)].
(2) A resist 11 is formed on the conductor layer 3 in the resistance element formation region 5 [see FIG. 1 (c), FIG. 1 (c ')].
(3) After removing the conductor layer 3 and the resistance layer 2 in the portion 12 where the resist 11 is not formed by batch etching, the used resist 11 is removed [see FIG. 1 (d), FIG. 1 (d ')].

In the step (C-1), a predetermined portion of the conductor layer 3 is etched to expose the resistance layer 2 under the conductor layer 3. That is, the conductor layer 3 in the element electrode formation region 6 is left to form an element electrode, and the conductor layer 3 in the element electrode isolation region 7 is removed.
Step (C-1) can be performed, for example, by sequentially performing the following procedures (1) to (2).
(1) After forming the resist 13 on the wiring pattern 4 and the substrate 1, the resist 13 in the element electrode isolation region 7 is removed by patterning to form a resist 13 non-formed portion 14 [FIG. 1 (e), FIG. (See e ')].
(2) After etching the conductor layer 3 in the portion 14 where the resist 13 is not formed, the used resist 13 is removed [see FIG. 1 (f), FIG. 1 (f ')]. When etching the conductor layer 3, it is desirable to use an etchant that hardly etches the resistance layer 2.
As described above, by performing the steps (A-1), (B-1), and (C-1), the resistance element 8 including the conductor layer 3 and the resistance layer 2 to be element electrodes is formed on the substrate 1. .

The second method for incorporating the resistance element in the printed wiring board includes the following steps (A-2) to (B-2) (see FIGS. 2 to 5).
(A-2) A step of forming a patterned resistance layer 22 on the substrate 21.
(B-2) A step of forming a conductor layer 23 on the substrate 21.

Here, in the step (A-2), the resistance layer 22 is formed on the resistance element formation region 25 set on the substrate 21. The resistance element forming region 25 is set in an appropriate shape such as a rectangle or a meander structure so that a desired resistance value can be obtained. The substrate 21 is exposed outside the resistance element formation region 25.
When the resistance layer 22 is formed in the step (A-2), it is performed as an electroless plating step (a) in which a nickel / phosphorus thin film to be a resistance layer is formed using the above-described electroless nickel / phosphorous plating solution. The patterned resistance layer 22 may be formed by plating the resistance layer 22 on the entire surface of the substrate 21 and then removing unnecessary portions by etching or the like, or plating the resistance layer 22 only on necessary portions on the substrate 21. A forming method may be used.

The acid treatment step (b) may be performed at any stage after the resistance layer 22 is formed as long as the acid used for the acid treatment does not affect the conductor layer 23. In the case of a method in which the unnecessary layer is removed by etching after the resistance layer 22 is formed on the entire surface of the substrate 21, if the acid treatment is performed in a state where the resistance layer 22 is plated on the entire surface, the processing can be performed uniformly. preferable. In the case of the method in which the resistance layer 22 is formed only on the necessary portion, it is preferable that the acid used for the acid treatment can be freely selected regardless of the material of the conductor layer 23 before the conductor layer 23 is formed.
When the heat treatment step (c) is performed, it may be performed at any stage as long as it is after the acid treatment step (b), may be performed before the step (B-2), or may be performed in the step (B-2). ) May be followed. When trimming is performed, it is preferable to perform the heat treatment step (c) before the trimming step in order to suppress the influence of heat generated during trimming.

As a method of removing unnecessary portions by etching after forming the resistance layer 22 on the entire surface of the substrate 21, for example, the following steps (1a) to (4a) can be performed in order (FIG. 2). reference).
(1a) A resistance layer 22 is formed on the entire surface of the substrate 21 [see FIG. 2 (a)].
(2a) A resist 31 is formed on the resistance layer 22 in the resistance element formation region 25 [see FIG. 2 (b) and FIG. 2 (b ')].
(3a) The resistance layer 22 of the portion 32 where the resist 31 is not formed is removed by etching [see FIGS. 2 (c) and 2 (c ')].
(4a) The used resist 31 is removed [see FIG. 2 (d) and FIG. 2 (d ')].

As a first method of plating the resistance layer only on a necessary portion on the substrate, for example, the following procedures (1b) to (4b) can be sequentially performed (see FIG. 3).
(1b) Pd catalyst treatment (not shown) is performed on the entire surface of the substrate 21 [see FIG. 3 (a)].
(2b) A resist 33 is formed on the entire surface of the substrate 21 excluding the resistance element formation region 25 [see FIGS. 3B and 3B '].
(3b) The resistance layer 22 is formed by plating on the resist 33 non-formation portion 34 (that is, the resistance element formation region 25) of the substrate 21 [see FIGS. 3 (c) and 3 (c ')].
(4b) The used resist 33 is removed, and the substrate 21 is exposed to a portion other than the resistance element formation region 25 [see FIGS. 3D and 3D ′].

As a second method of plating the resistance layer only on a necessary portion on the substrate, there is a method of sequentially performing the following procedures (1c) to (3c) (not shown). This method utilizes the effect that plating is not deposited on the portion where the Pd catalyst has been removed.
(1c) After performing Pd catalyst treatment on the entire surface of the substrate, a resist is formed in the resistance element formation region.
(2c) After removing the Pd catalyst on the non-resist forming portion of the substrate with the Pd removing solution, the used resist is removed. By this treatment, the Pd catalyst is left only in the resistance element formation region.
(3c) A resistance layer is plated on the substrate. At this time, since the resistance layer is not deposited on the Pd catalyst removal portion on the substrate, the resistance layer is plated only in the resistance element forming region where the Pd catalyst is left.

The step (B-2) is a step of forming the two conductor layers 23 in the element electrode formation region 26 set so as to be in contact with the resistance layer 22 formed by patterning in the step (A-2). In order to separate the two conductor layers 23, the element electrode separation region 27 is set so as to overlap the resistance element formation region 25.
Step (B-2) can be performed, for example, by sequentially performing the following procedures (1d) to (5d) (see FIG. 4).
(1d) Pd catalyst treatment (not shown) is performed on the entire surface of the patterned resistance layer 22 and the exposed substrate 21 [see FIG. 4A].
(2d) A resist 41 is formed on the resistance layer 22 in the element electrode isolation region 27. At this time, the portion where the substrate 21 is exposed and the portion on the resistance layer 22 where the conductor layer 23 (element electrode) is formed are defined as the resist 41 non-formed portion 42 [FIG. 4B, FIG. ')reference].
(3d) After plating the conductor layer 23 on the portion 41 where the resist 41 is not formed on the substrate 21, the used resist 41 is removed [see FIG. 4 (c), FIG. 4 (c ′)].
(4d) A resist 43 is formed on the conductor layer 23 on the element electrode formation region 26 and the resistance layer 22 on the element electrode isolation region 27 [see FIG. 4 (d), FIG. 4 (d ′)].
(5d) After removing the conductor layer 23 in the resist 44 non-formed portion 44 by etching or the like, the used resist 43 is removed [see FIGS. 4 (e) and 4 (e ')].
As described above, the resistance element 28 including the resistance layer 22 provided in the resistance element formation region 25 and the conductor layer 23 (element electrode) provided in the element electrode formation region 26 is formed on the substrate 21.
In the method shown in FIG. 4, the resist 41 is removed after the formation of the conductor layer 23. Instead, this resist 41 is left, and in the step (4d), the conductor layer 23 and the resist 41 (plating resist) are removed. A resist 43 (etching resist) can be formed thereon. In this case, the step (3d) can be omitted.

As a 2nd method of performing a process (B-2), there exists the method of performing the following procedures (1e)-(5e) in order (refer FIG. 5).
(1e) A seed layer 24 is formed on the entire surface of the patterned resistance layer 22 and the exposed substrate 21. The seed layer 24 may be any conductive material, and is preferably copper, silver, nickel, or the like formed by electroless plating [see FIG. 5A].
(2e) A resist 51 is formed on the seed layer 24 except for the element electrode formation region 26 [see FIGS. 5B and 5B '].
(3e) The conductor layer 23 is formed by plating on the portion 52 where the resist 51 is not formed [see FIGS. 5 (c) and 5 (c ')].
(4e) The used resist 51 is removed. Thereby, the conductor layer 23 can be formed only in the element electrode formation region 26 [see FIG. 5 (d), FIG. 5 (d ')].
(5e) Excluding the seed layer 24 protected under the conductor layer 23, the excess seed layer 24 is removed by etching [see FIGS. 5 (e) and 5 (e ')]. Since the seed layer 24 is made of a conductive material, it is integrated with the conductor layer 23 to form an element electrode. In addition, since the excess seed layer 24 on the resistance layer 22 is removed in the element electrode isolation region 27, a short circuit between the conductor layers 23 due to the seed layer 24 does not occur.
As described above, the resistance element 28 including the resistance layer 22 provided in the resistance element formation region 25 and the conductor layer 23 (element electrode) provided in the element electrode formation region 26 is formed on the substrate 21.

According to the method for manufacturing a resistance element as described above, it is possible to obtain a resistance element that exhibits high electrical resistance characteristics even when placed in a heating environment, and can be formed with high accuracy in a small size. .
In the method shown in FIG. 5, when removing the seed layer 24 in the step (5e), the seed layer 24 must be removed but the resistance layer 22 should not be affected (etching). The method shown in FIG. 5 requires fewer steps than the method shown in FIG. 4, but it is difficult to set conditions for removing the seed layer 24, so that the resistance layer 22 is replaced with a resist 43 when the conductor layer 23 is etched. The method shown in FIG. 4 for covering and protecting is preferred. Note that the method shown in FIG. 5 can cope with the formation of finer wiring than the method shown in FIG.

Examples of the present invention and comparative examples will be described below.
In the following Examples and Comparative Examples, the sheet resistance value of the resistance layer is measured by a four-end needle method (Loresta MPMCP-T350 manufactured by Mitsubishi Chemical Corporation).

[Example 1]
An electroless nickel / phosphorous plating solution having the following composition was prepared.
・ Nickel sulfate hexahydrate 26g / L
・ Diethylenetriamine (complexing agent) 0.27 mol / L
・ Sodium hypophosphite monohydrate 30g / L
・ Lead nitrate 1mg / L
・ Ion exchange water remaining

A nickel / phosphorous thin film having a thickness of 0.5 μm is formed on a substrate 1 having a thickness of 0.4 mm made of a bismaleimide triazine resin (BT resin) under the conditions of a bath temperature of 80 ° C. and a pH of 6.0 using the above plating solution. The resistance layer 2 was formed on the entire surface [see step (A-1) and FIG. 1 (a)].
When the sheet resistance value immediately after the electroless plating of the obtained resistance layer 2 was measured, it was 200Ω / □.

An aqueous nitric acid solution having a concentration of 5% by volume was prepared using reagent grade nitric acid. The BT resin substrate 1 having the resistance layer 2 on the entire surface was immersed in the nitric acid aqueous solution at room temperature for 10 minutes to perform acid treatment.
When the sheet resistance value of the resistance layer 2 after the acid treatment was measured, it was 50467Ω / □.

After the acid treatment, the resistance layer 2 was subjected to a heat treatment at 200 ° C. for 30 minutes in order to stabilize the plating film. The sheet resistance value of the resistance layer 2 after the heat treatment was measured and found to be 170383 Ω / □.
On the resistance layer 2 subjected to the acid treatment and the heat treatment, about 0.3 μm was plated by an electroless copper process (Shipley Far East CU POSIT), and further about 10 μm was plated by electrolytic copper plating to form a conductor layer 3. [Refer to procedure (1) of process (B-1) and Drawing 1 (b)].

  A negative dry film resist 11 (manufactured by Hitachi Chemical Co., Ltd., RY-3215) was laminated on the conductor layer 3. Next, the resist 11 was exposed through a negative pattern (not shown) and selectively exposed with ultraviolet rays. The negative pattern was designed so that the resist 11 in the resistance element formation region 5 was exposed. The non-exposed portion of the resist 11 was removed at a temperature of 30 ° C. using a developing solution (1% aqueous sodium carbonate solution) [Procedure (2) in step (B-1), FIG. 1 (c), FIG. )reference].

  The conductive layer 3 exposed in the portion 11 where the resist 11 is not formed is etched away at 65 ° C. using an iron (III) chloride solution, and then the exposed resistance layer 2 is removed from a copper sulfate-sulfuric acid solution (copper sulfate 250 g / L, sulfuric acid). 5 ml / L) and etched away at 90 ° C. Next, the used resist 11 was removed using a stripping solution (5% aqueous sodium hydroxide solution). As a result, a wiring pattern 4 composed of the conductor layer 3 and the resistance layer 2 was formed in the resistance element formation region 5 [see step (B-1) in step (3), FIG. 1 (d), and FIG. 1 (d ′). ].

  A negative dry film resist 13 (manufactured by Hitachi Chemical Co., Ltd., RY-3215) was laminated on the conductor layer 3 and the exposed substrate 1. Next, the resist 13 was exposed through a negative pattern (not shown) and selectively exposed with ultraviolet rays. The negative pattern was designed such that the resist 13 was exposed in a region excluding the device electrode isolation region 7. The non-exposed portion of the resist 13 was removed at a temperature of 30 ° C. using a developer (1% aqueous sodium carbonate solution) [Procedure (1) in step (C-1) and FIGS. 1 (e) and 1 (e ′)]. )reference].

The conductive layer 3 in the resist 13 non-formed portion 14 (that is, the element electrode separation region 7) was removed by etching using an alkaline etching solution (“A process” manufactured by Meltex Co., Ltd.). Next, the used resist 13 was removed using a stripping solution (5% aqueous sodium hydroxide solution) [see step (C-1) in step (2), FIG. 1 (f), and FIG. 1 (f ′)]. ].
Thus, the resistance element 8 having the resistance layer 2 and the two conductor layers 3 (element electrodes) formed in contact with the resistance layer 2 was manufactured on the substrate 1.
The obtained resistance element 8 exhibited high electrical resistance characteristics even when placed in a heating environment, and was excellent in thermal stability.

[Example 2]
An electroless nickel / phosphorous plating solution having the following composition was prepared.
・ Nickel sulfate hexahydrate 26g / L
・ Sodium L-glutamate (complexing agent) 0.4 mol / L
・ Sodium hypophosphite monohydrate 30g / L
・ Lead nitrate 1mg / L
・ Ion exchange water remaining

A nickel / phosphorous thin film having a thickness of 1.0 μm is formed on a substrate 21 having a thickness of 0.4 mm made of a bismaleimide triazine resin (BT resin) using the above plating solution under conditions of a bath temperature of 90 ° C. and a pH of 5.8. The resistance layer 22 was formed on the entire surface [see step (A-2), step (1a) and FIG. 2 (a)].
When the sheet resistance value immediately after electroless plating of the obtained resistance layer 22 was measured, it was 31Ω / □.

An aqueous nitric acid solution having a concentration of 5% by volume was prepared using reagent grade nitric acid. The BT resin substrate 21 having the resistance layer 22 formed on the entire surface was immersed in the nitric acid aqueous solution at room temperature for 10 minutes to perform acid treatment.
When the sheet resistance value of the resistance layer 22 after the acid treatment was measured, it was 88640Ω / □.
After the acid treatment, in order to stabilize the plating film, the resistance layer 22 was subjected to a heat treatment at 200 ° C. for 30 minutes. It was 70300 ohm / square when the sheet resistance value of the resistance layer 22 after heat processing was measured.

  On the resistance layer 22 subjected to the acid treatment and the heat treatment, a negative dry film resist 31 (manufactured by Hitachi Chemical Co., Ltd., RY-3215) was laminated. Subsequently, the resist 31 was selectively exposed by irradiating ultraviolet rays through a negative pattern (not shown). The negative pattern was designed so that the resist 31 except the desired resistance element formation region 25 was exposed. After the exposure, the non-exposed portion of the resist 31 was removed using a developer (1% aqueous sodium carbonate solution) at a temperature of 30 ° C. for 60 seconds. The resist 31 remained in the exposed portion, and a patterned resist 31 covering the resistance element forming region 25 was obtained [see step (A-2), step (2a), FIG. 2 (b), FIG. 2 (b ')] .

The resistance layer 22 of the resist 31 non-formation portion 32 is removed by etching at 90 ° C. using a copper sulfate-sulfuric acid solution (copper sulfate 250 g / L, sulfuric acid 5 ml / L) to expose the substrate 21 outside the resistance element formation region 25. [See step (A-2), step (3a), FIG. 2 (c), FIG. 2 (c ′)].
Next, the used resist 31 was removed using a stripping solution (5% aqueous sodium hydroxide solution). Thus, the patterned resistance layer 22 was formed in the resistance element formation region 25 on the substrate 21 [see step (A-2), step (4a), FIG. 2 (d), and FIG. 2 (d ')].

  A Pd catalyst (not shown) was applied to the entire surface of the substrate 21 having the patterned resistance layer 22 [see step (B-2) procedure (1d) and FIG. 4 (a)]. A negative dry film resist 41 (manufactured by Hitachi Chemical Co., Ltd., RY-3215) was laminated thereon. Subsequently, the resist 41 was selectively exposed by irradiating ultraviolet rays through a negative pattern (not shown). The negative pattern was designed such that the resist 41 on the patterned resistance layer 22 was exposed. After the exposure, the unexposed portion of the resist 41 was removed using a developer (1% aqueous sodium carbonate solution) at a temperature of 30 ° C. for 60 seconds. The resist remained in the exposed portion, and a patterned resist 41 covering the device electrode isolation region 27 was obtained [see step (2d) in step (B-2) and FIG. 4 (b)].

  About 0.3 μm was plated on the resist 42 non-formed part 42 using an electroless copper plating solution (manufactured by Meltex Co., Ltd., CU-390), and further plated by electrolytic copper plating to about 10 μm to form a conductor layer 23. The used resist 41 was removed using a stripping solution (5% aqueous sodium hydroxide solution) [see step (B-2), procedure (3d) and FIG. 4 (c)].

  A negative dry film resist 43 (manufactured by Hitachi Chemical Co., Ltd., RY-3215) was laminated on the resistance layer 22 and the conductor layer 23. Subsequently, the resist 43 was selectively exposed by irradiating ultraviolet rays through a negative pattern (not shown). The element electrode formation region 26 is set so that the conductor layer 23 is separated into two portions in contact with the resistance layer 22, and the resist 43 on the element electrode formation region 26 and the element electrode separation region 27 is exposed in the negative pattern. Designed as follows. After the exposure, the non-exposed portion of the resist 43 was removed using a developer (1% aqueous sodium carbonate solution) at a temperature of 30 ° C. Thus, the resist 43 was patterned so as to protect the resistance layer 22 exposed in the element electrode isolation region 27 and the conductor layer 23 in the element electrode formation region 26 [Procedure (4d) in step (B-2) and FIG. (See (d)).

The conductor layer 23 of the resist 43 non-formed portion 44 was removed by etching at 65 ° C. using an iron (III) chloride solution, and an element electrode was formed by the conductor layer 23 left in the element electrode formation region 26. Next, the used resist 43 was removed using a stripping solution (5% aqueous sodium hydroxide) [see step (B-2) in step (5d) and FIG. 4 (e)].
Thus, the resistance element 28 having the resistance layer 22 and the two conductor layers 23 (element electrodes) formed in contact with the resistance layer 22 was manufactured on the substrate 21.
The obtained resistance element exhibited high electrical resistance characteristics even when placed in a heating environment, and was excellent in thermal stability.

[Comparative Example 1]
An electroless nickel / phosphorous plating solution having the following composition was prepared.
・ Nickel sulfate hexahydrate 26g / L
・ Sodium citrate (complexing agent) 0.2 mol / L
・ Sodium hypophosphite monohydrate 30g / L
・ Lead nitrate 1mg / L
・ Ion exchange water remaining

Resistance comprising a nickel / phosphorus thin film having a thickness of 1.0 μm on a 0.4 mm thick substrate made of a bismaleimide triazine resin (BT resin) under the conditions of a bath temperature of 85 ° C. and a pH of 6.0 using the above plating solution. A layer was formed on the entire surface.
When the sheet resistance value immediately after electroless plating of the obtained resistance layer was measured, it was 4.5Ω / □.

An aqueous nitric acid solution having a concentration of 5% by volume was prepared using reagent grade nitric acid. The BT resin substrate having the resistance layer on the entire surface was immersed in the aqueous nitric acid solution at room temperature for 10 minutes for acid treatment.
When the sheet resistance value of the resistance layer after the acid treatment was measured, it was 4.2Ω / □.

After the acid treatment, the resistance layer was subjected to a heat treatment at 200 ° C. for 30 minutes.
When the sheet resistance value of the resistance layer after the heat treatment was measured, it was 4.1 Ω / □.
In the same manner as in Example 1, a resistance element having a resistance layer and two conductor layers (element electrodes) was manufactured. A resistance element manufactured using a complexing agent that is not an amino group-containing compound has poor electrical resistance characteristics.

  The present invention can be used, for example, as a resistance element built in a printed wiring board.

In the manufacturing method of the resistance element of this invention, it is process drawing explaining an example of the method of implementing process (A-1), (B-1), (C-1). It is process drawing explaining an example of the method of performing a process (A-2) in the manufacturing method of the resistive element of this invention. It is process drawing explaining the other example of the method of performing a process (A-2) in the manufacturing method of the resistive element of this invention. In the manufacturing method of the resistance element of this invention, it is process drawing explaining an example of the method of performing a process (B-2). It is process drawing explaining the other example of the method of performing a process (B-2) in the manufacturing method of the resistive element of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,21 ... Board | substrate, 2,22 ... Resistance layer, 3,23 ... Conductor layer, 4 ... Wiring pattern, 8, 28 ... Resistance element.

Claims (9)

In a method for manufacturing a resistance element including an element electrode and a resistance layer,
(A) Electroless plating method using an electroless nickel / phosphorous plating solution containing a complexing agent which is a nickel salt, a reducing agent and an amino group-containing compound (wherein the amino group is —NH ₂ and / or> NH) An electroless plating process for forming a resistance layer on the substrate by
(B) an acid treatment step of subjecting the resistance layer to an acid treatment;
A method of manufacturing a resistance element, comprising:   2. The method of manufacturing a resistance element according to claim 1, wherein after the acid treatment step (b), (c) a heat treatment step of performing a heat treatment on the resistance layer is performed.   The method of manufacturing a resistance element according to claim 2, wherein the heat treatment (c) is performed within a range of 100 to 850 ° C.   4. The method of manufacturing a resistance element according to claim 1, wherein the resistance layer has a sheet resistance value at 200 ° C. of 20 Ω / □ or more. In a method for manufacturing a resistance element including an element electrode and a resistance layer,
(A-1) forming a resistance layer on the entire surface of the substrate by plating;
(B-1) forming a wiring pattern comprising the resistance layer and the conductor layer after forming a conductor layer on the substrate;
(C-1) etching a predetermined portion of the conductor layer to expose a resistance layer under the conductor layer;
Comprising the step of forming the resistance layer,
(A) Electroless plating method using an electroless nickel / phosphorous plating solution containing a complexing agent which is a nickel salt, a reducing agent and an amino group-containing compound (wherein the amino group is —NH ₂ and / or> NH) An electroless plating process for forming a resistance layer on the substrate by
(B) an acid treatment step of subjecting the resistance layer to an acid treatment;
A method of manufacturing a resistance element, comprising:   6. The method of manufacturing a resistance element according to claim 5, wherein after the acid treatment step (b), (c) a heat treatment step of performing a heat treatment on the resistance layer is performed. In a method for manufacturing a resistance element including an element electrode and a resistance layer,
(A-2) forming a patterned resistance layer on the substrate;
(B-2) forming a conductor layer on the substrate;
Comprising the step of forming the resistance layer,
(A) Electroless plating method using an electroless nickel / phosphorous plating solution containing a complexing agent which is a nickel salt, a reducing agent and an amino group-containing compound (wherein the amino group is —NH ₂ and / or> NH) An electroless plating process for forming a resistance layer on the substrate by
(B) an acid treatment step of subjecting the resistance layer to an acid treatment;
A method of manufacturing a resistance element, comprising:   The method of manufacturing a resistance element according to claim 7, wherein after the acid treatment step (b), (c) a heat treatment step of performing a heat treatment on the resistance layer is performed. In a method for manufacturing a resistance element including an element electrode and a resistance layer,
(A) Electroless plating method using an electroless nickel / phosphorous plating solution containing a complexing agent which is a nickel salt, a reducing agent and an amino group-containing compound (wherein the amino group is —NH ₂ and / or> NH) An electroless plating process for forming a resistance layer on the substrate by
(B) an acid treatment step of subjecting the resistance layer to an acid treatment;
A resistance element formed by a process comprising:

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