JP2017224663A - Method of manufacturing magnetic recording apparatus and magnetic recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a magnetic recording apparatus capable of reducing loss of data and damage of element destruction which are caused due to heat during a reflow process without increasing the size of the magnetic recording apparatus, and a magnetic recording apparatus.SOLUTION: A method of manufacturing a magnetic recording apparatus according to an embodiment of the present invention includes a reflow process which includes: a first step of providing a heat insulating material on a surface of a magnetic recording apparatus, the surface being exposed to the inside of a reflow furnace; a second step of passing the magnetic recording apparatus with the heat insulating material through the reflow furnace to heat the magnetic recording apparatus; and a third step of removing the heat insulating material from the magnetic recording apparatus having been heated.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a method for manufacturing a magnetic recording apparatus and a magnetic recording apparatus.

  In recent years, a magnetic random access memory (MRAM) using a tunnel magnetoresistive effect (TMR) has been used as a magnetic storage device having characteristics such as non-volatility, high speed, and long-term reliability. Proposed. A recording medium such as a memory needs to be subjected to a high-temperature process because there is a process of mounting before becoming a product. When a high temperature process such as a reflow process is performed, the magnetoresistive effect element has problems such as destruction of the magnetoresistive effect element and inability to hold data due to damage such as data loss or element destruction due to heat. Further, there may be a problem that the damage due to heat remains and the magnetoresistive element is easily broken and the quality is deteriorated. In order to solve this problem, for example, Japanese Patent Application Laid-Open No. 2014-36192 proposes a nonvolatile semiconductor memory device including an envelope having a heat insulating region.

JP 2014-36192 A

  In the envelope described in Patent Document 1, since the size of the magnetic recording device becomes large, covering the whole increases the cost. An object of the present invention is to provide a method of manufacturing a magnetic recording apparatus and a magnetic recording apparatus that can reduce data loss and element damage due to heat in a reflow process without increasing the size of the magnetic recording apparatus. .

  In order to solve the above problems, a method of manufacturing a magnetic recording device according to the present invention includes a first step of providing a heat insulating material so as to contact a surface exposed in a reflow furnace of the magnetic recording device, and a magnetic recording including the heat insulating material. The apparatus comprises a reflow process including a second step of heating the magnetic recording apparatus by passing the apparatus through a reflow furnace and a third step of removing the heat insulating material from the heated magnetic recording apparatus.

  The method for manufacturing a magnetic recording device having the above characteristics suppresses the temperature rise of the magnetoresistive element in the reflow furnace by providing a heat insulating material so as to be in contact with the surface exposed in the reflow furnace of the magnetic recording device, and data It is possible to suppress the rewriting and destruction of elements.

  In order to solve the above problems, the method for manufacturing a magnetic recording apparatus according to the present invention is characterized in that the heat insulating material is a foam.

  In the method for manufacturing a magnetic recording device having the above characteristics, the thermal conductivity of the heat insulating material is lowered by using a foam as the heat insulating material so as to be in contact with the surface exposed in the reflow furnace of the magnetic recording device. As a result, the temperature rise of the magnetoresistive effect element in the reflow furnace can be further suppressed, and rewriting of data and destruction of the element can be suppressed.

  In order to solve the above problems, the method for manufacturing a magnetic recording apparatus according to the present invention is characterized in that the heat insulating material is in a gel form.

  In the method for manufacturing the magnetic recording device having the above characteristics, the heat insulating material in contact with the surface exposed in the reflow furnace of the magnetic recording device is gelled, so that the adhesion rate of the heat insulating material is increased, and the heat insulating material in the reflow process is increased. Prevent peeling. In addition, since the thermal conductivity is lowered, the temperature rise of the magnetoresistive effect element in the reflow furnace can be further suppressed, and data rewriting and element destruction can be suppressed.

  In order to solve the above problems, the method of manufacturing a magnetic recording apparatus according to the present invention is characterized in that the heat insulating material has a boiling point higher than normal temperature and lower than the maximum temperature in the reflow furnace.

  In the method of manufacturing the magnetic recording apparatus having the above characteristics, the heat insulating material is vaporized in the reflow furnace because it has a boiling point that is higher than normal temperature and lower than the maximum temperature in the reflow furnace. Thereby, heat of vaporization is generated, and the temperature rise of the magnetoresistive effect element in the reflow furnace can be further suppressed, and rewriting of data and destruction of the element can be suppressed.

  In order to solve the above-described problems, a method of manufacturing a magnetic recording device according to the present invention includes providing a heat insulating material so that the magnetic recording device is covered with a heat insulating material so that at least a terminal portion in contact with the land is exposed. Features.

  In the method of manufacturing the magnetic recording device having the above characteristics, the temperature transmitted from the terminal is also reduced by covering the terminal portion in contact with the land with a heat insulating material so as to be exposed at least. As a result, the temperature rise of the magnetoresistive element in the reflow furnace can be further suppressed, and the effect of suppressing data rewriting and element destruction can be improved.

  In order to solve the above problems, the magnetic recording apparatus according to the present invention is in a state where the heat insulating material is left unburned on the surface exposed to the reflow furnace of the magnetic recording apparatus after the heat insulating material passes through the reflow furnace. It is characterized by.

  In the magnetic recording apparatus having the above characteristics, the surface area of the magnetic recording apparatus can be increased because the heat insulating material remains unburned. As a result, the heat generated when the magnetic recording apparatus operates can be dissipated, and the possibility of erasing recorded data can be reduced.

  The present invention provides a method of manufacturing a magnetic recording apparatus and a magnetic recording apparatus that can reduce the loss of data and damage to elements due to heat in a reflow process without increasing the size of the magnetic recording apparatus.

Sectional drawing of the magnetic-recording apparatus which provided the heat insulating material in the surface based on 1st Embodiment Sectional drawing of the reflow process which concerns on 1st Embodiment Sectional drawing of the magnetic-recording apparatus which provided the heat insulating material in the surface based on 2nd Embodiment

  Preferred embodiments for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those that are equivalent. Furthermore, the constituent elements described below can be appropriately combined. In addition, various omissions, substitutions, or changes of components can be made without departing from the scope of the present invention.

(First embodiment)
[Magnetic recording device]
FIG. 1 is a cross-sectional view of a magnetic recording apparatus in which a heat insulating material is provided on the surface according to the first embodiment. The magnetic recording apparatus 1 includes a semiconductor magnetic memory 2, an IC package 3, and a terminal 4. The semiconductor magnetic memory 2 is covered with an IC package 3 having terminals 4. A heat insulating material 7 is provided on the surface exposed in the reflow furnace of the magnetic recording apparatus 1. The magnetic recording apparatus 1 is electrically connected by fixing the terminals 4 and the lands 6 on the substrate 5 with solder 8.

  For example, an MRAM can be used as the semiconductor magnetic memory 2. In particular, the semiconductor magnetic memory 2 is suitable for those using magnetization reversal, such as STT-MRAM, which reverses the magnetization direction of the magnetic material by flowing spin-polarized electrons through the magnetic material. The semiconductor magnetic memory 2 is mounted on a substrate 5 or the like for use as a product. When mounting on the substrate 5, the solder 8 is melted and connected to the substrate 5.

  The semiconductor magnetic memory 2 is generally sealed with resin, and the semiconductor magnetic memory 2 sealed with resin is mounted on the substrate 5 as an IC package 3. However, the semiconductor memory 2 may be directly mounted on the substrate 5 and the semiconductor memory 2 may be resin-sealed. There is also such a packaging method, and the resin sealing method is not limited. The IC package 3 has a plurality of terminals 4 in order to improve the number of signal lines and the connection with the substrate 5. The terminal 4 may be any terminal that can electrically connect the magnetic recording apparatus 1 and the substrate 5. For example, a terminal that protrudes in one direction such as the SIP type, a terminal that protrudes in two directions such as the DIP type, a terminal that protrudes in four directions such as the QFP type, A back terminal such as a CSP may be used. As a material of the terminal 4, gold, silver, copper, an alloy containing them, or the like is preferable.

  For the resin sealing, a thermosetting resin or the like can be used. The resin used for resin sealing of the IC package 3 is, for example, an epoxy resin.

  The substrate 5 only needs to be configured to be electrically connected to the terminal 4 coming out of the IC package 3. The substrate 5 may be a printed wiring board, a flexible substrate, or the like depending on the intended use. Examples of the material of the substrate 5 include glass epoxy, polyimide, and ceramic.

[Reflow process]
The reflow process may be a process for electrically connecting a component such as an IC and the substrate 5. Other than the connection using solder, any process that can electrically connect the component and the substrate using a reflow furnace may be used. The process of putting the magnetic recording apparatus 1 into the reflow furnace and mounting it on the substrate 5 will be described below with reference to FIG.

[First step]
Before the magnetic recording apparatus 1 is put into the reflow furnace, the heat insulating material 7 is provided on the surface exposed to the reflow furnace of the magnetic recording apparatus 1. In order to fix the terminal 4 and the land 6, solder 8 is provided between the terminal 4 and the land 6. As the solder, lead-free solder or low-temperature solder that rides on the land 6 is used, and is composed of, for example, an alloy of tin, silver, and copper.

  A foam can be used as the heat insulating material 7 provided on the surface exposed in the reflow furnace of the magnetic recording apparatus 1. By forming the heat insulating material 7 in the form of foam, it is possible to further suppress the temperature rise in the reflow furnace of the magnetic recording apparatus 1 and to suppress data rewriting and element destruction.

  The foam means a material containing bubbles. In the foam, it is preferable that the bubbles are dense and at least all of the bubbles do not disappear in the reflow furnace. The foam includes a foam insulating material, a hollow structure insulating material, and the like. Examples of the foam insulating material include polystyrene, silicon, and PTFE, and examples of the hollow structure insulating material include a hollow structure fluororesin. Examples of the shape of the foam include solid, liquid solidified, and liquid. Among these, a foam that solidifies liquid is preferable because it is solidified after being in close contact with the IC package 3 and does not flow down from the surface of the IC package 3. However, it is not limited to them.

  Further, a gel-like heat insulating material can be used as the heat insulating material 7 provided on the surface exposed in the reflow furnace of the magnetic recording apparatus 1. By using the gel heat insulating material 7, the adhesion rate of the heat insulating material 7 is increased, and the heat insulating material 7 is prevented from being peeled off during the reflow process. Moreover, the temperature rise in the reflow furnace of the semiconductor magnetic memory 2 can be further suppressed, and the effect of suppressing data rewriting and element destruction can be improved.

  The gel form means that it is solidified in a jelly form with some elasticity and hardness. It has a high viscosity and is closely attached so that there is no gap between the IC package 3 and the gel heat insulating material 7. It is desirable that the connected terminal 4 is not covered. The gel-like heat insulating material 7 is, for example, PVA gel.

  Further, as the heat insulating material 7 provided on the surface exposed in the reflow furnace of the magnetic recording apparatus 1, a vaporizing material having a boiling point higher than normal temperature and lower than the maximum temperature in the reflow furnace can be used. If the heat insulating material 7 has a boiling point higher than normal temperature and lower than the maximum temperature in the reflow furnace, it evaporates at a temperature higher than normal temperature and lower than the maximum temperature in the reflow furnace, thereby generating heat of vaporization and reflowing the semiconductor magnetic memory 2. Temperature rise in the furnace can be further suppressed, and data rewriting and element destruction can be suppressed.

  What has a boiling point higher than normal temperature and lower than the maximum temperature in the reflow furnace means that the boiling point is higher than normal temperature and lower than the maximum temperature in the reflow furnace, and therefore vaporizes within that temperature. It is desirable that it is in close contact with 3. The heat insulating material 7 having a boiling point above normal temperature and below the maximum temperature in the reflow furnace is provided on the surface of the magnetic recording apparatus 1, and is, for example, flux.

  The heat conductivity of the heat insulating material 7 is preferably 0.5 W / mK or less. The heat insulating material 7 includes, for example, a low density material, a low thermal conductivity resin, a low thermal conductivity inorganic material, and the like.

[Second step]
Next, FIG. 2 is a diagram showing a reflow process for soldering the magnetic recording apparatus 1 to the substrate. The magnetic recording apparatus 1 is electrically connected and fixed on the substrate 5 by melting the solder 8 with the heater 10 in a reflow process in which the belt 9 moves in the reflow furnace.

  The belt 9 is provided in the reflow furnace in order to pass the magnetic recording apparatus 1 through the reflow furnace.

  The heater 10 becomes a heat source in the reflow furnace. As the heater 10 is heated, the temperature in the reflow furnace rises. A general reflow furnace is divided into a preheating zone, a main heating zone, and a cooling zone, and the main heating zone is a zone for applying the maximum temperature in the reflow furnace.

  For example, a temperature of about 260 ° C. is actually applied to the magnetic recording apparatus 1 in a reflow furnace. This temperature is equal to or higher than the melting point of commonly used lead-free solder, and the solder 8 is passed through a reflow furnace in order to melt the solder 8 by heat treatment at the melting point or higher. As a result, a temperature of 260 ° C. is also applied to the magnetoresistive effect element formed in the semiconductor magnetic memory 2. When a temperature as high as 260 ° C. is applied to the magnetoresistive effect element, the magnetoresistive effect element is liable to cause rewriting of data or destruction of the element. Here, the solder 8 has been described as a lead-free solder, but depending on the type of solder, there is a low-temperature solder having a melting point around 200 ° C. The reflow temperature may be higher than the melting point of the solder to be used.

  The heat insulating material 7 provided on the surface of the magnetic recording apparatus 1 before the reflow process may be covered with at least a part of the surface of the magnetic recording apparatus 1. It is sufficient that the magnetoresistive effect element in the semiconductor magnetic memory 2 is not broken.

[Third step]
After the reflow process, the heat insulating material 7 on the magnetic recording apparatus 1 is removed. In the removing step, the heat insulating material itself may be intentionally eliminated. For example, the heat insulating material 7 may be removed after the main heating zone is exceeded by the temperature of the reflow furnace during the reflow process. Also, a chemical method such as flux removal or a physical method may be used. Further, most of the removed heat insulating material 7 may be removed, and the heat insulating material 7 may not be completely removed from the magnetic recording apparatus 1.

  If the heat insulating material 7 remains unburned, the surface area of the magnetic recording apparatus 1 can be increased. By increasing the surface area, it is possible to reduce the possibility of erasing recorded data due to heat generated when the magnetic recording apparatus 1 operates. As a material of the heat insulating material 7, an organic material or the like is preferable.

  As a method of remaining unburned, a circular shape or a similar shape such as a curved shape, a shape that can be drawn with a single stroke, a polka dot pattern, a polygon such as a rectangle or a square, or a similar shape is preferable. It is sufficient if there is any unburned residue on the surface exposed in the reflow furnace of the magnetic recording apparatus 1.

(Second Embodiment)
The difference between the second embodiment and the first embodiment is that a jig is used to prevent data loss and element destruction damage.

  FIG. 3 is a cross-sectional view showing a case where the magnetic recording apparatus is covered with a heat insulating material 7 so that a terminal portion in contact with the land is at least exposed. When the heat insulating material 7 provided on the surface exposed in the reflow furnace 9 of the magnetic recording apparatus 1 exposes at least the portion of the terminal 4 in contact with the land 6 and is fixed with the substrate 5 and the solder 8, it can be electrically connected. ing.

  That the IC package 3 is covered with the heat insulating material 7 so that at least the terminals 4 are exposed means that the terminals 4 are covered with the heat insulating material 7 except for the portion fixed by the solder 8. For example, the heat insulating material 7 is preferably a solid jig or the like because it is not preferable to enter the portion fixed by the solder 8. Thereby, the temperature transmitted from the terminal 4 in the reflow process is reduced, the temperature rise in the reflow furnace of the semiconductor magnetic memory 2 can be further suppressed, and the effect of suppressing data rewriting and element destruction can be improved. .

  As shown in FIG. 3, the jig can cover the terminals 4 other than the portion fixed by the IC package 3 and the solder 8, and can reduce the heat applied to the semiconductor magnetic memory 2. This jig can be removed after the reflow process. For example, heat in the reflow furnace is prevented from directly hitting the IC package 3. As shown in FIG. 3, it is preferable that there is an air layer between the IC package 3 as shown in FIG. 3, but the IC package 3 may be in contact with the jig.

  The material constituting the jig is preferably an organic material, an insulating material, or a material containing bubbles. Since these materials have poor thermal conductivity, the temperature does not easily rise in the reflow process and are suitable for jigs.

  In the second embodiment, the reflow process is performed as in the first embodiment. Since it is the same as that of 1st Embodiment, the description is abbreviate | omitted.

  As the heat insulating material 7 provided on the surface exposed in the reflow furnace of the magnetic recording apparatus 1, the heat insulating material 7 is used so that at least the portion of the terminal 4 in contact with the land 6 is exposed. While the heat insulating material 7 exposes the terminal 4 and the other is covered with the heat insulating material 7, the adhesion rate of the heat insulating material 7 is increased, and the temperature increase in the reflow furnace of the magnetic recording apparatus 1 is further suppressed. By reducing the conduction heat transmitted from the terminal 4, it is possible to improve the effect of suppressing data rewriting and element destruction.

  As described above, according to the present embodiment, there is provided a method for manufacturing a magnetic recording apparatus that can reduce data loss and element damage due to heat in a reflow process without increasing the size of the magnetic recording apparatus.

  Although the preferred embodiment of the present invention has been described, it is possible to change the embodiment in addition to the embodiment described above. For example, in the embodiment, the soldering process has been described. However, instead of the soldering process, a drying process using a reflow furnace may be used.

  The present invention can be applied to a method of manufacturing a magnetic recording apparatus and a magnetic recording apparatus that can reduce data loss and element damage due to heat in a reflow process without increasing the size of the magnetic recording apparatus.

DESCRIPTION OF SYMBOLS 1 Magnetic recording device 2 Semiconductor magnetic memory 3 IC package 4 Terminal 5 Board | substrate 6 Land 7 Heat insulating material 8 Solder 9 Belt 10 Heater

Claims (6)

A first step of providing a heat insulating material on the surface exposed in the reflow furnace of the magnetic recording device;
A second step of heating the magnetic recording device by passing the magnetic recording device including the heat insulating material through the reflow furnace;
A method of manufacturing a magnetic recording apparatus, comprising: a reflow process including a third step of removing the heat insulating material from the heated magnetic recording apparatus.   2. The method of manufacturing a magnetic recording apparatus according to claim 1, wherein the heat insulating material is a foam.   2. The method of manufacturing a magnetic recording device according to claim 1, wherein the heat insulating material is in a gel form.   4. The method of manufacturing a magnetic recording apparatus according to claim 1, wherein the heat insulating material has a boiling point above normal temperature and below the maximum temperature in the reflow furnace. 5.   2. The method of manufacturing a magnetic recording device according to claim 1, wherein the heat insulating material is provided so that the terminal portion in contact with the land is covered with the heat insulating material so as to be exposed at least. .   The magnetic recording apparatus according to claim 1, wherein after the heat insulating material passes through the reflow furnace, the heat insulating material remains unburned on a surface exposed to the reflow furnace.

Images