JPH026052A - Electric heating member - Google Patents

Abstract

PURPOSE:To prevent the breaking of wiring due to the shunting of a current by successively covering the contact part of a heating member with a material to be worked with a coating film having specified resistivity and a specified contact angle to the melt of a metal consisting essentially of one out of lead and tin. CONSTITUTION:At least the contact part with a lead wire on the surface of a base material consisting of a conductive material is covered with a coating film consisting of a material having resistivity of >=100 times that of the base material and >=10 deg. contact angle to the melt of a metal consisting essentially of one out of lead and tin. Since at least the contact part of the heating member with the lead wire of an IC is thus covered with the insulating coating film having poor solder wettability, the breaking of wiring due to the shunting of a current from the heating member to the wiring of the substrate and the deposition of solder on the heating member are prevented.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention is directed to an energizing heating member that processes a workpiece such as a lead wire by applying electricity to an electrically conductive substance and generating Joule heat. Regarding.

(Conventional technology) In recent years, advances in factory automation have been remarkable.

An example of this is a device that solders integrated circuits (rc) to a substrate.This device uses Fe, MO, W, Ta,
Conductive materials such as Cu, AI, Ste)/less etc. ττ/)S
Soldering is performed by applying electricity to a heating member that has been processed from an I-shaped base material to generate Joule heat, and pressing a plurality of lead wires against the board at once with the heating member.

Usually, ICs have lead wires coming out on all sides, so
Two or four heating members are installed in parallel or surrounding them on all sides, and are electrically connected in series.

They may be connected in parallel, but in this case, the current capacity required during device shutdown increases.

When soldering is carried out by directly contacting the heating member made of a conductive material with the lead wires of the IC, the wiring of the board from the heating member connects the heating members connected in series. There was a problem in which the current was shunted to the circuit board, causing the wiring on the board to break. Another problem was that solder was difficult to adhere to the heating member.

(Problem that Umei is trying to solve) As mentioned above, when soldering is performed by directly contacting the heating member made of a conductive material to the lead wires of an IC, the current flows from the heating member to the wiring on the board. There were problems such as shunts, wires breaking, and solder adhering to heating elements.

In the present invention, at least the portion of the heating member in contact with the IC lead wires is coated with a coating made of a material that is insulative and has poor wettability with solder, making it difficult for solder to adhere to it. Wire breakage due to shunt current and soldering to heating components? The purpose was to prevent kidney damage and provide good processing.

[Structure of the Invention] (Means for Solving the Problems) The electrical heating member of the present invention has a surface of a base material made of an electrically conductive material, at least a portion in contact with a lead wire, which has a specific resistance of 10Of8 of the base material. It is characterized by being coated with a film made of a material having the above properties and having a contact angle with a molten metal containing at least one of lead or tin as a main component at 10 degrees or more.

The material of the coating coated on the surface of the heating member is C,
A material containing at least one element selected from O, N, etc. is used. The reason for this is as explained below. First, the coating must be made of a material that does not peel off from the base material when subjected to heat cycles from about 150°C to about 300°C. In addition, in O1-mation soldering equipment, the temperature of the heating member is raised and lowered at intervals of about several seconds, so the material of the coating must have high thermal conductivity. Therefore, if the film thickness of the film exceeds 1 μm, the heat conduction is 1W.
Must be more than m-lH-s (J).

All of the materials containing the above-mentioned elements have high heat conductivity.

In addition, ++[1 thermal material is 1 to 10i with respect to the earth potential.
Since there is a potential difference of 100°C, the film needs to have a thickness that prevents the insulating film from forming against this voltage. Therefore, the thickness of the second coating is preferably 500 mm or more.
ooÅ or more is necessary, and considering wear resistance of 14μ
mP 1 degree is necessary. Considering thermal conductivity [,1, 5μ
It is not preferable to make it more than m. Examples of methods for coating the surface of the base material with the film include sputtering and ion blasting.

Examples include vacuum evaporation, plasma CVD, ECR plasma CVD, thermal CVD, and optical CV [). Among these, we consider that the film has good adhesion, that it can be processed at a relatively low temperature without damaging the film's properties, and that the electrical properties of the film are easy to control11.
1! In this case, plasma CVD method and ECR plasma CVD method are particularly suitable.

(Function) By coating at least the portion of the heating member that is in contact with the lead wire C with an insulating film that has poor wettability with solder, the problem of solder adhering to the heating member is eliminated.

(Example) The heating member of the present invention is formed by processing a conductive material as shown in FIG.

In the A-tomage soldering device, these heating members are installed so as to surround them on all sides as shown in Figure 2, and they are electrically connected in series to a 50Hz AC power source. used.

The processing steps are as shown below. After the IC is placed on the board and transported, the heating member comes down and presses the lead wire of the IC with a pressure of about 2 to 9 folds/cm2. A current of 50OA is supplied and heated to about 300°C.

After the solder is melted and the lead wires and the circuit on the board are connected,
When the electricity is turned off and the solder hardens, the heating member is raised and this process is completed.

Hereinafter, an embodiment will be described in which a heating member of the present invention is mounted by coating the surface of a base material made of a conductive substance with an insulating film having poor wettability with solder.

Example 1 - In this example, a * film of the components shown in Table 1 was coated on the surface of a base material by plasma CVD.

FIG. 3 is a schematic diagram of a parallel plate type capacitively coupled "plasma CD device. A flat ground electrode 7 and a high frequency 'Fi pole 8 are placed facing each other in a vacuum chamber 6. The vacuum chamber 6 is provided with a gas inlet 12. A heater 9 is attached to the ground electrode 7).
(Connected to ill.

Using this apparatus, the conductive heating member was first coated with a film.

The conductive heating member 13 is placed on the ground electrode 7, and the inside of the chamber 6 is heated to 10-6 Torr by a vacuum pump (not shown).
Exhaust to culm. Next, the heater 9 attached to the installed electrode 7
The heating member 13 is heated from 150'C to about 459°C, and the gas inlet 12 is heated 3i to 1. +, N2, C
A raw gas such as Hn was supplied into the chamber 6, and the chamber 6 was evacuated so as to maintain the degree of vacuum within the chamber 6 at 0.05.times.-1.0 T. When power is applied to the high frequency electrode 8,
A glow discharge occurs between the electrodes, the raw material gas is turned into plasma, and the heating member 13 is coated with an insulating film. The components, raw material gas, and film forming conditions of the 'fIi film are as shown in Table 1. For example, when forming a film with a Si CN composition, Si H4100SCCM is used as the raw material gas.

N2500S CCM, Ct-14400S
CCM is introduced through the gas inlet 12, and the reaction pressure inside the chamber 6 is set to 1. Maintain at QTorr and apply 5 to high frequency electrode 8.
Film formation was performed by applying a voltage of 00 W. In this case, a film with a thickness of 3.0 μm was formed in a film formation time of 40 minutes.

Below, the components of the insulating film formed similarly for films of other components, the raw material gas and its flow rate, the reaction pressure in the chamber,
Power applied to the high frequency electrode 8.

The film formation time and film thickness are as shown in Table 1.

(Left below) According to the plasma CVD method, the heating member is heated to 150°C to 4°C.
Since it can be processed at a relatively low temperature of 50'C, a good film with strong adhesion strength to the base material can be produced without impairing the properties of the heating member.

Example 2 - In this tN example, a film containing the components shown in Table 2 was formed by sputtering. The sputtering apparatus used is as shown in FIG. A flat ground electrode 7 and a high frequency electrode 8 are installed facing each other in the vacuum chamber 6, and a heater 9 is attached to the flat ground electrode 7. The high-rise Itt electrode 8 is connected to a high frequency electrode 11 via a matching box 10. vacuum chamber 6
A gas inlet 12 is provided in the side wall of the gas inlet 12 . In this way, the sputtering apparatus is similar to the plasma CVD apparatus described above, but the only difference is that the high-frequency electrode 8 is provided with a solid raw material as the target 14. In order to form the first P-phobic film using this apparatus, first, a solid raw material was set up as the target 14, and Ar gas and optionally a reaction gas were simultaneously introduced through the gas inlet 12. These gases turn into plasma and Ar ions reach the target 14.
After ejecting the substance in atomic or molecular form,
A 9IAI film was formed on the surface of the heating member 130 while reacting in the plasma of the reactive gas. Table 3 lists the components, raw materials, film forming conditions, etc. of the film formed. For example, to form a film made of amorphous silicon, use g2M of single crystal or polycrystalline silicon as a target, introduce Ar gas IO8CCM and H2 gas 11005CC from the gas inlet 12, and increase the chamber pressure to 1X10-
The film was formed by applying a voltage of 500 W to 3 Torr (τ, 9 to 8 high frequency).

In this case, the film formation time was 3.0 minutes for 60 minutes. An amorphous silicon film with a thickness of 1 um was deposited. In addition, A as a raw material gas
At the same time as R gas and H2 gas, 1 SCCM of B2 H6 gas or 13 CCM fi of PH3 gas may be used for 34 people. Similarly, regarding the 'Ii film of the following pond components, the target solid, the raw material gas and its flow, the reaction pressure in the chamber 6,
Power applied to the high frequency electrode 8, film formation time and V of film formation
The A thickness is listed in Table 3.

(Left below) The sputtering method is easy to handle because it can use a solid as a raw material, and it can be said to be a versatile method since there is no need to change the shape of the device depending on the shape of the heating member.

Actual Example 3 - In this example, a film was formed on the surface of the base material by the ECR plasma CvD method. The equipment used in this method is
As shown in the figure. A gas inlet 12 is provided in FIη of the film forming space 15 .

In addition, a plasma formation chamber 16 is arranged above the Seisukoku 15.
And this film formation! 16 is in communication with the plasma inlet 118 provided on the partition plate 17. A quartz plate 19 is arranged on the upper wall of the plasma formation=16, and the quartz plate 1
A microwave waveguide 20 is arranged above the two.

In addition, the plasma formation chamber 16. A gas inlet 21 is provided on the upper wall, and an electromagnet 22 is provided around the plasma formation 916.
is provided.

To coat the heating member with an insulating film using this device,
The heating member 13 was installed at the bottom of the film forming chamber 15, and the film formation and deposition were carried out as follows. The inside of the film forming chamber 15 is evacuated by a vacuum pump, and the raw material gas is introduced into the film forming chamber 15 from the a introducing tube 12 maintained at a vacuum level of IXl, O-5 to 1 x 10-3.
In the plasma formation chamber, reaction gas (N2.02, Cl-
14, etc.), or gases (Ar, 1-1e, H2) that supply energy to others without causing any reaction in the card itself were introduced, respectively.

Microwave 4@:H20J: 2.45GHz microwave to form plasma! 16, this microwave generates an electric field E. Further, by passing a current through the electromagnet 22, 875 forms a magnetic field B within plasma formation=16. Electrons within the plasma formation space 16 resonate and are excited. When the electrons are introduced from the introduction pipe 21 by resonance, their energy is supplied to the N2 or Herr gas, forming a plasma of these gases. As the magnetic field increases, this plasma flows from the plasma outlet tube 18 until the film is formed.
It is withdrawn on 5th. Seiha! The components of l gas introduced from the introduction pipe 12 into il'15 are N! A film was formed on the surface of a flat heating member 13 in N 15. The raw material gas, film forming conditions, etc. for each film are listed in Table 5. For example, 3
When forming a film with an i4N component, S is used as a raw material.
i H41105CC was introduced through the gas inlet, and N250SCCM was introduced as a reaction gas through the gas inlet. The pressure inside the chamber is 3x 10” Tor
The microwave power was set to 500W. in this case,
Film formation time is 40 minutes! FI3. O! 71 films of Il were obtained. Below, the coatings of other components are also listed in Table 5 in the same section 1. 15, the reaction pressure, microwave power, film formation time, and thickness of the sample were made into two rules.

(Left margin of Ll) As described above, according to the ECR plasma CVD method, processing can be performed without heating the heating member, and a film having uniform components and adhering to the member can be formed.

Before performing the film formation shown in the above implementation θ11 to 3, Ar
Ion bombardment can increase the degree of adhesion between the coating and the base material. To carry out this process, in the case of the plasma CVD method and the ECR plasma CVD method, it is sufficient to flow Ar to form a plasma without supplying the original gas that forms the film, and in the case of the spuckling method, Instead, power should be applied to the base material.

Furthermore, in order to increase the degree of adhesion between the fusuma surface and the base material, it is recommended to form a region containing nitrogen slate, carbon mixture, atomization, etc. in a larger amount than the base material at the interface between the liquid film and the base material. Ion nitriding in advance,
The base material that has been carburized is coated with an insulating film, and during the ion bombardment, the gas is filled with N2.02
, Cl-14, etc. may be mixed.・Also, N2.02
, CH4, or other gases may be ion bombarded.

In this way, by coating the surface of the base material made of conductive material with a film made of a material that is insulating and has poor wettability with solder, there is no shunting of current from the heating member to the circuit of the board, resulting in good processing. Furthermore, it is possible to provide a heating member that is resistant to solder adhesion, has excellent wear resistance and oxidation resistance, and can withstand tens of thousands of uses.

[Effect 1 of the Invention] As described in detail below, according to the heating member of the present invention, the heating member is made of a material that is adhesive and has poor wettability with solder. There is no current shunt to the wire, and there is less solder adhesion, resulting in good processing.

[Brief explanation of the drawing]

1 to 5 all relate to embodiments of the present invention, FIG. 1 is a perspective view of one heating member, and FIG. 2 is a perspective view of one heating member.
Form drawing showing how several heating members are connected in series, No. 3
Figures 5 to 5 show the apparatus 'J1' for manufacturing a filler member.
18, FIG. 3 is a schematic diagram of an apparatus used in the plasma CVD method, FIG. 4 is a schematic diagram of an apparatus used in a sputtering method, and FIG. 5 is a schematic diagram of an apparatus used in an ECR plasma CVD method. be. 13... Heating member

Claims (1)

[Claims] In a member that processes a workpiece by heating it by applying electricity to a base material made of a conductive substance, at least the part of the base material that comes into contact with the workpiece has a specific resistance of 100 times or more that of the base material and is made of lead or tin. 1. An electrically heated member characterized in that it is sequentially coated with coatings having a contact angle with a molten metal of at least one of them as a main component of 10 degrees or more.