JP2000100839A - Method of sealing semiconductor element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of sealing a semiconductor element which enables easy and cheap supply of miniature semiconductor devices, wherein the outflow of liquid resin fed on an upper face of an insulating substrate is prevented effectively to seal a semiconductor element on the upper face of the insulating substrate with cured sealing-resin of a specified shape and thickness. SOLUTION: In sealing a semiconductor element 2 placed on an insulating substrate 1 with resin 8, the upper face of the insulating substrate 1 on which the semiconductor element 2 is placed is covered with liquid resin 6, and the temperature of the liquid resin 6 on a central region of the insulating substrate 1 is raised as compared to the outer region to make the viscosity of the liquid resin 6 covering the central region lower than 500 poises and the viscosity of the liquid resin 6 covering the outer region higher than 500 poises. Then, the liquid resin 6 is cured by heat or light. Outflow of the liquid resin 6 from the insulating substrate 1 can be prevented effectively, and the semiconductor element 2 and the upper face of the insulating substrate 1 can be sealed with cured resin 8 which has specified shape, specified thickness, and satisfactory flat plane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for covering an insulating substrate on which a semiconductor element is mounted with an upper surface thereof together with the semiconductor element with a liquid resin, and then curing the applied liquid resin. The present invention relates to a method for sealing a semiconductor element for sealing the element.

[0002]

2. Description of the Related Art Conventionally, as a resin-encapsulated semiconductor device mounted on an information processing apparatus such as a computer, a semiconductor element is made of an electrically insulating material such as an aluminum oxide sintered body, and a semiconductor element is mounted at the center of the upper surface. A semiconductor element having a plurality of electrodes on a lower surface of the mounting portion using a rectangular flat plate-shaped insulating base having a plurality of wiring conductors extending from the mounting portion to the lower surface. It is mounted so that the wiring conductor of the insulating substrate is connected via bumps such as solder or gold, and a sealing resin such as an epoxy resin is provided on the upper surface of the insulating substrate so as to cover the semiconductor element. There is known a semiconductor device in which a semiconductor element is sealed with a hardened resin and a semiconductor element is sealed with the hardened resin.

As a method of manufacturing a plurality of such semiconductor devices at once, for example, Japanese Patent Application Laid-Open No. H10-150119 discloses a semiconductor device mounted on each chip mounting area of a package substrate sheet having a plurality of chip mounting areas. The chip is mounted, and the entire surface of the package substrate is covered with a liquid resin material having a viscosity such that the surface is entirely flat, for example, an epoxy resin, and the liquid coating material is cured. There has been proposed a method of manufacturing a semiconductor device in which a semiconductor chip is divided in units of a semiconductor chip by cutting a back surface of a substrate sheet.

In such a semiconductor device, a portion of the wiring conductor protruding from the lower surface of the insulating base is brought into contact with the connection conductor of the external electric circuit board, and the wiring conductor and the connection conductor of the external electric circuit board are connected via solder. By bonding, the electrodes are mounted on an external electric circuit board, and at the same time, the respective electrodes of the semiconductor element are electrically connected to the external electric circuit via wiring conductors.

In order to apply a sealing resin such as an epoxy resin on the upper surface of the insulating base so as to cover the semiconductor element, after mounting the semiconductor element on the upper surface of the insulating base, for example, A method has been adopted in which a liquid resin, which is a precursor of an epoxy resin, is dropped so as to cover the semiconductor element, and then the liquid resin is heated to a temperature of about 150 ° C. and thermally cured.

In this case, since the liquid resin applied to the upper surface of the insulating base covers the semiconductor element mounted on the upper surface of the insulating base in a good and flat surface, the liquid resin to be applied is usually applied. Viscosity of about 100 to 500 poise (po
The liquid resin has sufficient fluidity as low viscosity as ise).

[0007]

However, when such a low-viscosity liquid resin is applied to the upper surface of the insulating substrate so as to cover the semiconductor element, the liquid resin applied has a good fluidity due to the good fluidity of the liquid resin. Spreads greatly on the upper surface of the insulating base, and a part thereof flows out from the outer peripheral portion of the upper surface of the insulating base, and it is difficult to seal the upper surfaces of the semiconductor element and the insulating base with a resin having a predetermined shape and thickness. There was a problem of becoming.

Therefore, conventionally, as proposed in, for example, Japanese Patent Application Laid-Open No. Hei 10-92979, a frame-shaped dam member for preventing the liquid resin from flowing out is provided on the outer peripheral portion of the upper surface of the insulating base. The liquid resin is dropped on the inside of the member to prevent the liquid resin applied to the upper surface of the insulating base from flowing out, or a wide area extending to a range where the liquid resin spreads is provided on the outer peripheral portion of the insulating base. Thus, some measures have been taken to prevent the liquid resin from flowing out.

However, when a dam member is provided on the outer peripheral portion of the upper surface of the insulating base, there is a problem that the manufacture of the semiconductor device becomes complicated and the semiconductor device becomes expensive. In addition, if a wide area is provided on the outer peripheral portion of the insulating base so as to extend to a range where the liquid resin spreads, it is necessary to increase the size of the insulating base accordingly.
For this reason, there have been problems such as an increase in the size of the semiconductor device and an extra material cost.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to effectively prevent the liquid resin applied to the upper surface of an insulating substrate from flowing out, thereby enabling the semiconductor device and the upper surface of the insulating substrate to be effectively removed. The present invention provides a method for sealing a semiconductor element which can be sealed with a hardened sealing resin having a predetermined shape and thickness, and can provide a small-sized semiconductor device simply and inexpensively.

[0011]

A method of sealing a semiconductor device according to the present invention is a method of sealing a semiconductor device mounted on an upper surface of an insulating substrate with a resin, wherein the semiconductor device is sealed. A liquid resin is applied on the upper surface of the mounted insulating base, and then the liquid resin is covered with the liquid resin so as to cover the central area of the insulating base by raising the temperature of the central area of the insulating base higher than the outer peripheral area. Is set to 500 poise or less, and the viscosity of the liquid resin covering the outer peripheral region is set to 600 poise or more, and thereafter, the liquid resin is cured by heat or light.

According to the method of sealing a semiconductor device of the present invention,
When the liquid resin is applied to the upper surface of the insulating base on which the semiconductor element is mounted and covers the upper surface of the insulating base together with the semiconductor element, the temperature of the central area of the insulating base is set higher than that of the outer peripheral area to cover the central area. The temperature of the outer peripheral region of the insulating substrate is set to be relatively high so that the viscosity of the applied liquid resin is 500 poise or less, and the viscosity of the liquid resin applied to the outer peripheral region is 600 poise or more. Since the liquid resin is deposited at a relatively low temperature, the liquid resin has a low viscosity of 500 poise in the central region of the insulating base and is easy to flow, so that the liquid resin makes the semiconductor element excellent and the surface of the liquid resin flat. In addition to being able to cover, the liquid resin has a viscosity of 600 poise or more and is difficult to flow in the outer peripheral region of the insulating base. It is possible to effectively prevent the easily liquid resin from flowing out from the outer peripheral portion of the upper surface of the insulating base.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the accompanying drawings.

FIGS. 1A to 1C are cross-sectional views showing an example of an embodiment of a method of sealing a semiconductor device according to the present invention for each step. In FIG. 1, reference numeral 1 denotes an insulating base, and 2 denotes a semiconductor element.

First, as shown in FIG. 1A, an insulating base 1 on which a semiconductor element 2 is mounted on an upper surface is prepared.

The insulating substrate 1 is made of ceramics such as aluminum oxide sintered body, aluminum nitride sintered body, mullite sintered body, silicon carbide sintered body, silicon nitride sintered body, etc. A substantially rectangular flat plate made of an electrically insulating material such as a composite material obtained by bonding an insulating resin and an inorganic insulating powder with an organic resin, and a plurality of semiconductor elements 2 are mounted on the upper surface thereof.

If the insulating substrate 1 is made of, for example, an aluminum oxide sintered body, an organic binder and a solvent, a plasticizer, and a dispersant suitable for aluminum oxide and raw material powders of silicon oxide, magnesium oxide, calcium oxide, etc. The mixture is added and mixed to form a slurry, and the slurry is formed into a ceramic green sheet by using a sheet forming method such as a well-known doctor blade method. Thereafter, an appropriate punching process is performed on the ceramic green sheet. And laminating a plurality of them and firing at a temperature of about 1600 ° C.

Further, the insulating base 1 is provided with, for example, tungsten or molybdenum.
A wiring conductor 3 made of a sintered metal powder such as copper or silver or a metal foil is applied.

The wiring conductor 3 functions as a conductive path for electrically connecting each electrode of the semiconductor element 2 to an external electric circuit. The electrodes of the semiconductor element 2 are connected to the upper surface of the insulating base 1 via bumps 4 made of, for example, gold or solder. Further, a portion led out to the lower surface of the insulating base 1 is connected to a connection conductor of an external electric circuit board (not shown) via solder.

If the wiring conductor 3 is made of, for example, a sintered body of tungsten powder, a conductor paste obtained by adding an appropriate organic binder and a solvent / plasticizer to the tungsten powder is mixed with the insulating base 1. The ceramic green sheet is printed and applied in a predetermined pattern, and is fired at the same time as the ceramic green sheet serving as the insulating substrate 1 so as to be drawn out from the upper surface to the lower surface of the insulating substrate 1.

In order to mount the semiconductor element 2 on the upper surface of the insulating base 1, a bump 4 made of gold, solder, or the like is applied to the electrode of the semiconductor element 2 in advance by pressure bonding or welding. A method is adopted in which the bumps 4 attached to the electrodes of the semiconductor element 2 are brought into contact with the wiring conductors 3 led out to the upper surface of the insulating base 1 and the bumps 4 and the wiring conductors 3 are joined by crimping or welding.

Next, as shown in FIG. 1B, a heater block capable of separately heating a central region and an outer peripheral region of the insulating substrate 1 on which the semiconductor element 2 is mounted is provided. Place on top of 5. Then, the liquid resin 6 covering the central region of the insulating substrate 1 is heated to a relatively high temperature at a temperature higher than that of the outer peripheral region so that the liquid resin 6 has a viscosity of 500 poise or less so that it can easily flow. At a lower temperature, 60 parts of the liquid resin 6
A liquid resin 6 which is a precursor of a thermosetting resin or a photocurable resin is discharged from the resin dropping nozzle 7 onto the upper surface of the insulating substrate 1 by dropping the liquid resin 6 onto the upper surface of the insulating substrate 1 at a relatively low temperature so as to have a viscosity of not lower than Poise. Then, the insulating substrate 1 is attached so as to cover the upper surface thereof.

When the thermosetting resin is an epoxy resin, for example, the liquid resin 6 may be a bisphenol type, a glycidyl ester type, a phenol novolak type or the like, and an acid anhydride type, an amine type or an imidazole type. It contains a curing agent and a filler such as silicon oxide powder.

The application of the liquid resin 6 by the resin dripping nozzle 7 is performed by discharging the liquid resin 6 while moving one resin dripping nozzle 7 along the upper surface of the insulating substrate 1. The liquid resin 6 may be dropped so as to spread over the entire surface. Alternatively, a number of the resin dripping nozzles 7 are evenly arranged on the upper surface of the insulating base 1 and the liquid resin 6 is discharged from the plurality of resin dripping nozzles 7 at the same time, so that the liquid resin 6 may be dropped.

In the present invention, the temperature of the central region of the insulating substrate 1 is set higher than that of the outer peripheral region such that the viscosity of the liquid resin 6 covering the central region becomes lower than 500 poise. It is important that the temperature of the outer peripheral region of the insulating base 1 be set to a relatively high temperature such that the viscosity of the liquid resin 6 covering the outer peripheral region is as high as 600 poise or more.

Here, the curing reaction of the liquid resin 6, which is a precursor of the thermosetting resin, rapidly starts at a certain temperature or higher. Until the curing reaction starts rapidly, the viscosity generally decreases as the temperature increases, and on the contrary, the viscosity increases as the temperature decreases. Therefore, by adjusting the types and molecular weights of the main agent and the curing agent, and the amount of the curing agent and the filler added, for example, the temperature at which the curing reaction starts rapidly is 50 ° C. and the temperature is relatively high, such as 30 ° C. to 50 ° C. At a temperature of less than 500 poise,
At a relatively low temperature of 28 ° C. or less, a liquid resin 6 having a high viscosity of 600 poise or more is prepared, and the temperature of the liquid resin 6 is set to a relatively high temperature of 30 ° C. to 50 ° C. in the central region. At the same time, if the liquid resin 6 covering the central region of the insulating substrate 1 is made to have a low viscosity of 500 poises or less, the liquid At the same time, the viscosity of the liquid resin 6 covering the outer peripheral region of the insulating base 1 can be made as high as 600 poise or more.

Of course, the temperature of the outer peripheral region of the insulating base 1 does not need to be extremely low so that the liquid resin 6 hardly exhibits fluidity.

Similarly, when the liquid resin 6 is a precursor of the photocurable resin, the liquid resin 6 has a property of decreasing the viscosity when the temperature is increased, and has the property of increasing the viscosity when the temperature is decreased. ing. Therefore, by adjusting the types and molecular weights of the main agent and the curing agent, and the amounts of the curing agent and the filler, etc., the temperature of the central region of the insulating base 1 is made higher than that of the outer peripheral region, as in the case of the thermosetting resin. By setting the temperature to be high, the viscosity of the liquid resin 6 covering the central region of the insulating base 1 can be reduced to 500 poise or less, and at the same time, the viscosity of the liquid resin 6 covering the outer peripheral region of the insulating base 1 can be set to 600 poise. The above high viscosity can be obtained.

As described above, the temperature of the central region of the insulating base 1 is set higher than that of the outer peripheral region where the viscosity of the liquid resin 6 covering the central region is as low as 500 poise or less. By setting the temperature of the region to a temperature lower than that of the central region where the viscosity of the liquid resin 6 covering the outer peripheral region has a high viscosity of 600 poise or more, the liquid resin covering the central region in the central region of the insulating substrate 1 6 is viscosity 500
Low viscosity below poise and easy to flow. Therefore, the semiconductor element 2 can be covered with the liquid resin 6 having a viscosity of 500 poise or less so that the surface becomes a flat surface satisfactorily.

On the other hand, at the outer peripheral portion of the insulating substrate 1, the liquid resin 6 covering the outer peripheral region has a high viscosity of 600 poise or more and is difficult to flow. The liquid resin 6 adhered to the upper surface of the insulating substrate 1 can be effectively prevented from flowing out from the outer peripheral portion of the upper surface of the insulating base 1.

Therefore, the central region and the outer peripheral region of the insulating substrate 1 are simply set to a predetermined temperature without providing a dam member or a large region for preventing the liquid resin 6 from flowing out in the outer peripheral region of the insulating substrate 1. By simply doing so, the semiconductor element 2 can be covered with the liquid resin 6 satisfactorily and the entire surface becomes a flat surface, and the liquid resin 6 can be prevented from flowing out of the outer peripheral portion.

If the temperature of the central region of the insulating substrate 1 is set to a relatively low temperature at which the viscosity of the liquid resin 6 covering the central region becomes higher than 500 poise, the liquid applied to the central region The fluidity of the resin 6 decreases, and it tends to be difficult for the liquid resin 6 to cover the semiconductor element 2 properly. Further, when the temperature of the outer peripheral region of the insulating base 1 is set to a relatively high temperature at which the viscosity of the liquid resin 6 covering the outer peripheral region becomes a low viscosity of less than 600 poise, the fluidity of the liquid resin 6 covering the outer peripheral region increases. It tends to be difficult to prevent the liquid resin 6 from flowing out from the outer peripheral portion of the upper surface of the insulating base 1.

Therefore, when the liquid resin 6 is applied to the upper surface of the insulating base 1 to cover the upper surface, the temperature of the central area of the insulating base 1 is increased by the viscosity of the liquid resin 6 applied to the central area. A relatively high temperature of 500 poise or less, preferably about 100 to 400 poise, is required.
Is required to be at a relatively low temperature so that the viscosity of the mixture is 600 poise or more, preferably about 700 to 3000 poise.

When the liquid resin 6 is applied to the upper surface of the insulating substrate 1, for example, the liquid resin 6 is first dropped onto the outer peripheral region of the insulating substrate 1, and then, is applied to the central region of the insulating substrate 1. If the liquid resin 6 is dropped, the viscosity of the liquid resin 6 dropped first on the outer peripheral region of the insulating substrate 1 becomes higher than 600 poise, and the viscosity dropped later on the central region of the insulating substrate 1. Low viscosity liquid resin 6 with 500 poise or less
Can be reliably prevented from flowing out of the outer peripheral portion of the insulating base 1.

Therefore, when the liquid resin 6 is applied to the upper surface of the insulating substrate 1, the liquid resin 6 is first applied to the outer peripheral region of the insulating substrate 1, and then the liquid resin 6 is applied to the central region of the insulating substrate 1. Preferably, the resin 6 is applied.

The heater block 5 for heating the insulating substrate 1 includes a central region heater block 5a for heating the central region of the insulating substrate 1 and an outer peripheral region heater for heating the outer peripheral region of the insulating substrate 1. And a central area heater block 5a.
What is necessary is just to make it possible to generate heat at different temperatures from the peripheral area heater block 5b. Further, when the heat in the central region of the insulating substrate 1 is transmitted to the peripheral region of the insulating substrate 1 and the peripheral region of the insulating substrate 1 does not reach a desired low temperature, for example, the peripheral region heater block 5b is cooled by water cooling or air cooling. A cooling function may be provided, and the outer peripheral region of the insulating base 1 may be actively cooled by the cooling function. By using such a heater block 5, it is possible to easily make the temperature of the outer peripheral region a desired low temperature while keeping the temperature of the central region of the insulating base 1 at a desired high temperature.

Finally, the liquid resin 6 adhered to the upper surface of the insulating base 1 so as to cover the semiconductor element 2 is heated to a temperature of, for example, about 150 ° C. by a heating device such as an oven and thermally cured. Alternatively, the semiconductor element 2 mounted on the upper surface of the insulating base 1 is irradiated with a curing light such as an ultraviolet light by an ultraviolet irradiation device such as an ultraviolet lamp to be light-cured, as shown in FIG. A semiconductor device sealed with the sealing resin 8 having a cured flat surface with a predetermined shape and a predetermined thickness is completed.

In this case, the liquid resin 6 whose flow has been settled after being once adhered to the upper surface of the insulating substrate 1 is removed from the insulating substrate 1.
A part of the resin is chemically bonded to the upper surface of the semiconductor element 2 and to the surface of the semiconductor element 2, and further flow is suppressed.
Therefore, even if the liquid resin 6 is heated again to thermally cure the liquid resin 6, the liquid resin 6 does not flow out from the outer peripheral portion of the upper surface of the insulating base 1.

Since the liquid resin 6 applied to the upper surface of the insulating substrate 1 does not flow out of the outer peripheral portion of the insulating substrate 1, the upper surfaces of the semiconductor element 2 and the insulating substrate 1 are formed to have a predetermined shape and thickness. It can be sealed with the cured resin 8.

In the outer peripheral region of the insulating base 1, there is provided a dam member, a wide area, and the like for preventing the liquid resin 6 applied to the upper surface of the insulating base 1 from flowing out from the outer peripheral portion of the upper surface. Since there is no need, the semiconductor device does not become large or expensive.

Thus, according to the method for sealing a semiconductor element of the present invention, the top surface of the semiconductor element 2 and the insulating base 1 is compact and sealed with the cured resin 8 having a flat surface having a good shape and thickness. A semiconductor device can be provided simply and inexpensively.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention. For example, in the example of the above-described embodiment, a plurality of semiconductor elements 2 are mounted on the insulating base 1, but one semiconductor element 2 may be mounted on the insulating base 1.

Further, a plurality of semiconductor elements 2
Is mounted and sealed with a cured resin 8, and then the insulating substrate 1 and the resin 8 are divided for each semiconductor element 2.
May be simultaneously and collectively obtained in a plurality of small semiconductor devices on which the semiconductor devices are mounted one by one.

Furthermore, in the above-described embodiment, the bumps 4 made of solder, gold, or the like are used as electrical connection means for connecting each electrode of the semiconductor element 2 to the wiring conductor 3.
A bonding wire made of aluminum, gold, or the like may be used as an electrical connection means for connecting each electrode of the semiconductor element 2 and the wiring conductor 3.

[0045]

EXAMPLE On a top surface of an insulating substrate made of an aluminum oxide sintered body having a size of 50 mm square and a thickness of 0.4 mm, 49 semiconductor elements having a size of 2.5 mm square and a thickness of 0.28 mm were vertically mounted.
It was mounted in a grid-like array of 7 rows × 7 rows. The distance between the semiconductor element in the outermost row and the outer peripheral area of the insulating base is 5.75 mm.
The distance between adjacent semiconductor elements was 3.5 mm.

Further, PANASEALER CV5765AK manufactured by Matsushita Electric Industrial Co., Ltd. was prepared as a liquid resin. This liquid resin contains a bisphenol-type epoxy resin base material, an acid anhydride-based curing agent, and a silicon oxide powder filler, and has a viscosity of 1000 poise at 25 ° C., 600 poise at 28 ° C.,
Viscosity at 30 ° C is 500 poise, viscosity at 40 ° C is 20
0 Poise. When the temperature exceeds 50 ° C., the curing reaction starts rapidly and the viscosity is increased. At 55 ° C., almost no fluidity is exhibited.

Further, a 3 mm gap is provided between the central area heater block and the central area heater block having a size of 36 mm square and 30 mm thick to form a frame-shaped outer peripheral area having a width of 7 mm and a thickness of 30 mm. A stainless steel heater block having a heater block was prepared. Note that the central area heater block and the outer peripheral area heater block can be separately heated, and a heat insulating material is disposed in a gap between the two. Further, a flow path through which cooling air passes is provided in the outer peripheral area heater block, and the insulating base on the outer peripheral area heater block can be cooled by passing the cooling air through this flow path.

Next, the insulating substrate on which the semiconductor element is mounted is placed on the heater block and heated so that the temperature of the outer peripheral region and the temperature of the central region of the insulating substrate become the temperatures shown in Table 1. The temperature is 25 ° C on the upper surface of this insulating base.
The liquid resin was dropped and applied so as to cover the upper surfaces of the semiconductor element and the insulating base. After standing for 3 minutes, the liquid resin was cured by heating to 150 ° C. in an oven, and the state of sealing with the resin was confirmed.

Table 1 shows the results. In Table 1, the methods of sample numbers 1 and 5 are out of the scope of the present invention.

[0050]

[Table 1]

As shown in Table 1, in the sealing method of the present invention of Sample Nos. 2, 3, and 4, no outflow of resin or generation of voids in the resin was obtained, and the semiconductor element was sealed well. On the other hand, in the method of No. 1 which is a method out of the scope of the present invention, voids which were considered to be due to insufficient fluidity of the liquid resin were confirmed in the resin in the central region. In the method of No. 5, outflow of the resin from the outer peripheral portion of the insulating base was observed.

When a silicon oxide powder filler was further added to the liquid resin used in this example, the viscosity at 25 ° C. could be as high as about 3000 poise. Also, by reducing the content of the silicon oxide powder filler, the viscosity at 40 ° C. could be reduced to about 100 poise.

[0053]

According to the semiconductor element sealing method of the present invention, when covering the upper surface of the insulating substrate on which the semiconductor element is mounted with the liquid resin, the temperature of the central region of the insulating substrate is higher than that of the outer peripheral region. To a relatively high temperature so that the viscosity of the liquid resin covering the central region is 500 poise or less, and the temperature of the outer peripheral region of the insulating base is set to 600 poise or more for the liquid resin covering the outer peripheral region. Since the liquid resin is applied at a relatively low temperature, the liquid resin has a low viscosity of 500 poise in the central region of the insulating base and is easy to flow. The surface can be covered so that the entire surface becomes a flat surface, and the viscosity of the applied liquid resin is high at 600 poise or more in the outer peripheral region of the insulating base, making it difficult to flow. As a result, it was possible to effectively prevent the applied liquid resin from flowing out of the outer peripheral portion of the insulating base. As a result, there is no need to provide a dam member or a wide area in the outer peripheral area of the upper surface of the insulating base, and the upper surfaces of the semiconductor element and the insulating base are sealed with a hardened sealing resin having a predetermined shape and a predetermined thickness. A small semiconductor device could be provided simply and inexpensively.

[Brief description of the drawings]

FIGS. 1A to 1C are cross-sectional views for explaining steps of a semiconductor device sealing method according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating base 2 ... Semiconductor element 6 ... Liquid resin 8 ... Hardened sealing resin

Claims (1)

[Claims] 1. A method of sealing a semiconductor element mounted on an upper surface of an insulating substrate with a resin, the method comprising: applying a liquid resin to an upper surface of the insulating substrate on which the semiconductor element is mounted; Next, of the liquid resin, the viscosity of the liquid resin covering the central region of the insulating substrate by raising the temperature of the central region of the insulating substrate higher than that of the outer peripheral region is 500 poise or less,
A method for sealing a semiconductor element, comprising setting the viscosity of the liquid resin covering the outer peripheral region to 600 poise or more, and thereafter curing the liquid resin by heat or light.