JPS58159393A - Method of producing semiconductor device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing a semiconductor device that can correct warpage of a substrate such as a hybrid integrated circuit.

[Technical background of the invention]

Generally, a semiconductor device such as a hybrid integrated circuit has a first
As shown in the figure, it has a substrate 1 in which alumina (Aj, 0.)n ceramic RVG x is formed by thermal spraying on the surface of a metal plate 10 made of aluminum or the like. In the table dik of this board 3, the circuit configuration 1 requires four bodies 1-4 and a resistor 5.
etc. are formed by thermal spraying or by Il) technology.

To prepare the substrate 3 as described above, first, the surface of the metal plate 1 is made into a rough surface with a roughness of, for example, 20 to 30 .mu.m, by printing or chemical etching. and,
A ceramic layer 2 is formed on the surface E of the metal plate 1 by thermal spraying (Detsuma thermal spraying). In this case, connected pores are formed in the ceramic layer 2. When these pores exist, moisture is absorbed. In this case, there is a disadvantage that the insulation between the conductor layer 4 formed on the metal plate 1 and the static layer 27 is reduced.

In order to eliminate this inconvenience, it is possible to hermetically seal the entire board 1 to prevent moisture from entering.
The hermetic sealing technique is magnetization, which increases the cost of shipping to Korea.Therefore, the method used by connoisseurs is to soak resin into the pores of the ceramic layer 2. In this method, a thermosetting resin is impregnated and the resin is cured at a temperature of, for example, 200 cfi degrees. On the substrate s having such a ceramic layer 2, the conductor layer 4 and the resistor 5 are formed as described above, and furthermore, as shown in FIG. In this case, the arm word transistor is fixed to the conductor layer 441 by soldering or the like via the @f lock 1 for heat radiation.

[Problems with background technology]

By the way, when the substrate 1 as mentioned above is made of general C;
Figure 43 (A)), based on the temperature when these two types of @te are combined, Figure 3 IB) I = As shown, if the temperature increases by t, the one with the larger coefficient of thermal expansion 1□ On the other hand, as shown in @3 Figure 1c), if the temperature decreases, birch will warp with am, which has a smaller coefficient of thermal expansion, on the outside. In this way, if the board 1 warps, for example, when 1 & 1 are placed on the heat sink 1 as shown in Figure 4),
Even if the board 1 is warped as shown in Fig. 4, the heat dissipated from the heat sink will cause a negative impact on the heat sink I. If 1 is flattened by the pressure of screwing, etc., this is not a big problem in terms of the heat dissipation effect E, but there is a problem in that an unnecessary load is applied to the board j itself. Also, if the board 1 itself is flat at room temperature, rhombus formation will not be a problem after mounting to the heat sink 1, but it will be a problem especially if the board 3 is warped at j1 temperature ct. .

It is thought that such warping of the spread plate J occurs in the following steps in the conventional manufacturing process as described below. Step 1 is a Nando Plast step to roughen the surface of the gold W4 plate 1 of the substrate 1. In this step, the surface of the gold plate 10 is roughened by spraying particles of alumina or the like, and at this time, the surface area of the surface of the metal plate 10 becomes large, so that the back surface is warped from the balance t. @2 is the process of thermal spraying ceramic on the surface of the metal plate 1, and when the gold+ll4f metal rises to L and returns to room temperature, the substrate S is placed with the tray and plate L inside.
This is the case when the material warps.

Further c, @3 is a warpage caused in the process of impregnating St resin into the pores of the ceramic layer 1 and curing it. In this case, if the resin can be cured at room temperature after being impregnated, the warping at room temperature will disappear, but
Considering the physical and mechanical properties, it is necessary to use a thermosetting resin that hardens at high temperatures. Therefore, at temperature TI (higher temperature than room temperature), a substrate 1 in which a gold tg plate 1 with a coefficient of thermal expansion α and a ceramic layer 2 impregnated with a resin with a coefficient of thermal expansion α, (α,〉α,) are combined. It is flat at temperature T, but when returned to room temperature d, it warps with the metal plate 1 inward (Figure 3 (C)).

[Purpose of the invention]

This invention was made in view of the circumstances mentioned above, and it corrects the warpage that occurs on the substrate during the manufacturing process of the hybrid circuit board, thereby producing a stable semiconductor device. An object of the present invention is to provide a method for manufacturing a semiconductor Mll that can be manufactured.

[aa* of the invention] That is, in the present invention, the pores 1 of the ceramic layer constituting the substrate are impregnated with a thermosetting resin, and the resin is thermosetted at a constant temperature. Then, the substrate resin is annealed at a higher temperature than fIAlf, which is a thermoset resin, to correct the warpage of the substrate.

[Example of actual failure of Tongmei]

An embodiment of the present invention will be described with reference to the drawings. Figures IA) and (B) are diagrams showing the manufacturing process of a substrate 1 such as a hybrid integrated circuit according to one embodiment of the present invention. That is, C to manufacture this substrate j is first made of gold such as pure aluminum (for example, the size is 330 x 330- and the thickness is 2.0 Am).
The surface of No. 1 is roughened by San-Y blasting so that it has an unevenness of about 20 to 30 μm.

The surface 1 of this gold IA temporary 1 is coated with a ceramic layer 2 (thickness of about 100-150μ) by thermal spraying (Hiroaki Detsuma) of alumina powder (A for 0.) with a particle size of 5 to 20μ, for example. form (Figure 5 Prisoner). Further, the substrate 3 is heated to a temperature of about 100° C., and then a thermosetting resin (for example, BT3103, manufactured by Gas Kagaku Co., Ltd.) is impregnated into the pores 11 of the ceramic mz, and 5 to 10 Leave it for about a minute (
Figure 5(B)). Next, l! of board 3! I! After removing 1° of the resin remaining on the surface, heating is performed at a temperature of about 200° C. for about 1 hour to harden the thermosetting resin 10.

After curing, the entire substrate 1 is heated at a temperature of about 360° C. for about 5 minutes, and then gradually cooled to room temperature.

In this way, the manufactured board 3 is, for example, 40×60-
After punching out the size, conductors 4114 and resistors 5 are formed on the substrate S as shown in the OLEM diagram to construct a hybrid integrated circuit or the like. by the way,
By impregnating the thermosetting resin 10 into the pores of the ceramic layer 1 of the second substrate 1 as described above and curing it, the substrate 1 is usually warped a (radius 67f of the substrate 3) as shown in FIG.
1) occurs at about 150 μm. Therefore, in the present invention, after the resin 10 is cured as described above, the entire substrate S is cooled down to the thermoset layer of the resin 10, that is, the heat treatment step is used to significantly reduce the above-mentioned warping of the substrate J. I can make one correct answer. Specifically, the scratchiness of the substrate 3 after straightening could be reduced to about 30 μm. Therefore, when circuit elements such as a power transition are installed in a heat sink on a 1u circuit with such warpage corrected, the board 3 is connected to the heat sink 1a at the center, and sufficient heat radiation is achieved. effect can be obtained.

By the way, in the manufacturing process described above, after forming the ceramic layer 2 on the base E of the 71 plate 1 and impregnating it with thermosetting property 1111, it was bent at a temperature of 150°C for 15 minutes, and heated to 200°C with a latch.
Heat at a temperature of 1 hour to harden the resin. Thereafter, a conductive layer (IEL) is formed on the surface of the substrate using a paste (for example, Meijin CP-OOJ manufactured by Asahi Chemical Co., Ltd.) in a predetermined pattern by screen printing. And 1
iii The entire substrate is heated to 300'G in elemental (N,) gas.
Perform annealing L7.

With this manufacturing method, it is possible to anneal the paste and straighten the warp of the board at the same time.
This has the effect of making it possible to check the efficiency of the manufacturing process.

Here, the results of correcting the warpage of the grave temporary formed by the above manufacturing method are shown in each persimmon resin and gold Tl.
The corpuscular mini is shown according to class 14 of lI4 plate. The numbers are @
As shown in Fig. 6, Shigenobu is μ in the long length of the crow, and the direction is shown in Fig. 7 (At, (as shown in Bl, the ceramic mJ If it is warped, it will be in one direction.

Table (1) (Metal plate is a corrosion-resistant aluminum plate) Table (2) (Metal plate is a pure aluminum plate) Time, further heated at a temperature of 200°C for 1 hour, and warp correction was performed at a temperature of 300°C for 5 minutes. As is clear from Table 1 (11, (2)), when the gold plate is a pure aluminum plate and the cured resin is BT2100, C
2. It can be corrected to minimize warpage. In this way, if the material of the metal plate and the impregnated resin are appropriately selected,
It is also possible to suppress the warpage of the board within a certain range. [Effects of the Invention] As detailed below, according to the present invention, the warpage that occurs on the board during the manufacturing process of boards such as heidelised integrated circuits can be suppressed. Warpage can be reliably corrected. Therefore, when a substrate provided with a circuit element such as a power transistor is attached to a heat sink, it is possible to obtain a sufficient heat dissipation effect.

[Brief explanation of drawings]

Figure 41 and i@2 are diagrams showing the configuration of a conventional semiconductor device, Figures 3 to 3 (C) are diagrams explaining the state of warpage of the curtain plate due to temperature changes, Figure 4 (TB)) A diagram showing the state when a conventional board is installed on a heat sink, #45 Figure 0 (
Embodiment I of the present invention: B) is a diagram illustrating the manufacturing process of such a semiconductor device; FIGS. DESCRIPTION OF SYMBOLS 1... Metal plate, 2... Ceramic mesh, 3... 4 Temporary, 4... Conductor layer, 5... Resistor, 5... Arm transistor, I... Heat dissipation Board, 10... thermosetting resin, 1... void. Dene person's agent Patent attorney Takeshi Suzue Hachi?

Claims (1)

[Claims] The process of forming a ceramic layer on the surface of the metal plate by thermal spraying, the process of impregnating the ceramic with the thermosetting resin 81ii and thermosetting the resin, and the substrate consisting of the gold I14 plate and the ceramic layer are performed. A method for manufacturing a semiconductor III, comprising the step of annealing at a temperature higher than the thermosetting temperature of the substrate to correct warpage of the substrate.