JPS60211068A - Formation of film - Google Patents

Abstract

PURPOSE:To form different film circuits simultaneously on both the surfaces of base plate by fitting the base plate to a rotary cylindrical base plate holder of the inside of a bell jar and providing targets respectively in opposing to the front and rear surfaces of the base plate. CONSTITUTION:A film hybrid integrated circuit is manufactured by forming a film circuit element with sputtering on both the front and rear surfaces of circuit base plate. Plural sheets of base plates 16, 17 for coating sputtered films are fitted to the outer and inner surfaces or a rotatable cylindrical base plate holder 11 or perforated holes 23 are provided to a base plate holder 21 and a base plate 22 is fitted therein and attached. The first target 12 is provided via a shutter 14 in opposing to the inner side base plate 16 or the inner surface of the base plate 22 and the second target 13 is provided via a shutter 15 in opposing to the outside base plate 17 or the outer surface of the base plate 22. The different sputtered films are formed to both the surfaces of said base plate or to one surface of two sheets of base plates by performing magnetron sputtering through removing the shutters 14, 15.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a method for forming a thin film, and particularly to a method for manufacturing a thin film hybrid integrated circuit in which thin film circuit elements are formed on both the front and back surfaces of a substrate.

(b) Background of the Technology Hybrid integrated circuits formed by forming and mounting circuit elements can be mass-produced to reduce manufacturing costs and ensure stable quality. However, while some products are produced in relatively small quantities, devices equipped with hybrid integrated circuits are becoming smaller. With the demand for higher density, higher integration is being promoted. Therefore, it is necessary to streamline the manufacturing process for small-volume products.In conventional hybrid integrated circuits, circuit elements were formed and mounted only on one side (front side) of the circuit board, but on the other side (back side). ), it has been considered to increase the degree of integration by forming and mounting circuit elements.

(C) Prior Art and Problems However, in the conventional sputtering apparatus, the sputtering source and the substrate holder face each other in a predetermined direction, making it impossible to form two types of films in the same Pelger. Therefore, it is disadvantageous for small-volume production products where the capacity of the equipment is available, and the double-sided hybrid integrated circuit requires repeating the manufacturing process of the single-sided hybrid integrated circuit, or, for example, rotating the substrate holder by 180 degrees in the Pel jar of the sputtering equipment. The circuit element forming film was deposited on one side at a time.

(d) Object of the Invention The object of the present invention is to provide a method for forming a thin film using a magnetron sputtering apparatus, which eliminates the above-mentioned problems,
The purpose of the present invention is to streamline the manufacturing process of thin film hybrid integrated circuits produced in small quantities, or to contribute to the practical application of thin film hybrid integrated circuits in which circuit elements are formed and mounted on both sides.

(e) Structure of the Invention The above object is to attach a substrate to the cylindrical surface of a cylindrical substrate holder that can be rotated or reversed, and to connect a first target for sputtering provided inside the cylindrical surface and This is achieved by a thin film sputtering method characterized in that two types of sputtering films are deposited on the substrate in the same bell jar using a second target for sputtering provided on the outside of the surface.

(f) Examples of the invention The present invention will be explained in detail below using the drawings.

FIG. 1 is a schematic diagram for explaining the outline of a magnetron sputtering apparatus. Magnetron sputtering equipment uses orthogonal electromagnetic fields to confine plasma moving according to Lorentz's equation in a local space near the target (cathode), and as a result of electrons moving cycloidally on the target colliding with gas molecules, the density decreases. This sputtering apparatus is characterized by generating high plasma to eliminate damage caused by electrons colliding with the sputtering substrate and to obtain a high sputtering rate.

In FIG. 1, 1 is a cylindrical substrate holder that can be rotated or reversed, 2 is a target made of the same material as the sputtered film material, and 3 is a rotatable substrate holder that appropriately partitions the space between the holder 1 and the target 2. The shutter 4 is a plurality of sputtered film-coated substrates attached to the outer cylinder surface of the holder 1. In general, a plurality of targets 2 (not shown), which are incorporated together with an anode electrode (not shown), a magnet for applying an orthogonal electromagnetic field (not shown), etc., face the outer cylindrical surface of the substrate holder 1.
For example, 3 pieces) are distributed and arranged.

The sputtered film deposited by such an apparatus, for example, the nichrome (NiCr) film deposited on the target-facing surface of the substrate 4 using the target 2 made of nichrome (NiCr), has almost the same composition as the target 2. , and can be deposited at low temperatures (for example, 80° C.). Therefore, the thermal shock received by the substrate 14 and the layer (film) already deposited is less than that of the conventional D
This is significantly less than a sputtering device called a C two-pole sputtering method or an RF (radio frequency) sputtering substrate.

FIG. 2 is a schematic diagram for explaining the outline of a magnetron sputtering apparatus according to an embodiment of the present invention.

In FIG. 2, 11 is a cylindrical substrate holder that can be rotated or reversed, 12 is a first target made of the same material as the first sputtered film material, and 13 is made of the same material as the second sputtered film material. second target, 14 is holder 1
1 is a rotatable first shutter that appropriately partitions the facing space between 1 and target eye 2; 15 is a holder 11 and target 1;
16 is a plurality of sputtered film coating substrates attached to the inside of the outer cylinder surface of the holder 11; 17 is a rotatable second shutter that appropriately partitions the space facing the holder 11
A plurality of sputtered film-covered substrates are attached to the outside of the outer cylindrical surface of.

Therefore, if the inert gas pressure inside the Pelger device is, for example, 7.
3 In an atmosphere of approximately
When the shutter 15 is opened so that the substrate 16 and the target 12 face each other and the substrate 17 and the target 13 face each other, a film having approximately the same composition as each opposing target 7) 12 or 13 is formed on the substrate 12, 13. be coated.

FIG. 3 shows a magnetron according to another embodiment of the present invention.
FIG. 1 is a schematic diagram for explaining the outline of a sputtering apparatus.

Parts that can be common with those in Fig. 2 have the same reference numerals (12, 13, 14).
In FIG. 3 using the holder 21, 21 is a cylindrical substrate holder that can be rotated or reversed, and 22 is a plurality of sputtered film-coated substrates attached to the holder 21, with the substrates 22 attached on the outside. Each board 21 is mounted on the holder 21.
A through hole 23 is drilled through which a predetermined portion of the back surface (mounting surface) is exposed.

Therefore, the substrate 22 on which the sputtered film is deposited using such an apparatus has a target 1 on the back surface facing the target eye 2.
On the other hand, a film having the same composition as target 13 is deposited on the surface facing target 13.

In addition, FIG. 4 is a schematic cross-sectional view showing an enlarged structure of the electrode layer formed on the thin film hybrid integrated circuit board, and FIG. 5 is a diagram showing the characteristics of the NiCr-Au electrode layer deposited by a magnetron sputtering device. FIG. 5(a) is a diagram showing the resistance-temperature characteristics of the lead terminal bonded to the electrode layer by thermocompression bonding means, and FIG. The tensile strength of the terminal is determined by actual measurements, and FIG. 5 (c) is a diagram determined by actual measurements of the solder erosion characteristics of the electrode layer.

In FIG. 4, 31 is a glazed substrate, 32 is a substrate 3
A tantalum (Ta) layer 33 is deposited on the upper surface of 1, and a gold (A
u) Layer 35 is formed and is an electrode layer.

In Figure 5 (a), the horizontal axis is the Ni component ratio % of the NiCr target used, and the vertical axis is the temperature coefficient T, C, Rppm.
/°C, the solid line A is the temperature characteristic of the electrode layer, which is obtained by plotting the measured values and connecting them with a curve, and the temperature characteristic A is approximately 60% Ni.
The electrode layer using NiCr target is ±0,
It increases before and after that. Therefore, Ni60% Ni
Considering the temperature characteristics of the electrode layer using a Cr target,
It will be the best.

In Figure 5 (El), the horizontal axis is the Ni component ratio % of the NiCr target used, the vertical axis is the tensile strength of the lead terminal bonded to the electrode layer, and the solid line B plots the measured values and draws them as a straight line. It is the tensile strength property connected by B-+
B-2 is the tensile strength characteristic when the electrode layer is heat-treated at 275°C for 5 hours, B-2 is the tensile strength property when the electrode layer is heat-treated at 250°C for 5 hours, and B is the tensile strength property when the electrode layer is heat-treated at 200°C for 5 hours. Tensile strength characteristics when heat treated, B-4 are tensile strength characteristics when the electrode layer is not heat treated. And while the tensile strength characteristic B-4 is a substantially constant value, each tensile strength characteristic B.

~B-3 shows the maximum value when using a NiCr target with approximately 60% Ni;
The electrode layer using the target is the most excellent in terms of tensile strength properties.

In Fig. 5 (c), the horizontal axis is the Ni component ratio % of the NiCr target used, and the vertical axis is the erosion of the solder deposited on the top surface of the electrode layer (Au is diffused into the solder and disappears).
%, the solid line C is the solder eating characteristic by plotting the measured values and connecting them with a straight line, C-1 is the characteristic at the first solder dip, C-z is the characteristic at the second solder dip, C-S shows the characteristics at the third solder dipping.

The electrode layer deteriorates each time the solder dip is repeated, but the solder erosion characteristic C of the electrode layer using a 70% Ni/NiCr target shows that the electrode layer deteriorates due to the first solder dip and the repeated solder dip. ,
It is clear from FIG. 3 (c) that this method is superior to the others.

Therefore, from FIG. 5(a) and FIG. 5(o), in order to create an electrode layer to which lead terminals etc. are connected by thermocompression bonding by magnetron sputtering, a NiCr target containing 160% N is used to create the best electrode layer. is obtained. On the other hand,
To create the electrode layer used for soldering by magnetron sputtering, as shown in Figure 5 (c), 70% Ni
The best electrodes can be obtained using a NiCr target.

Therefore, when the electrode layer 33 is bonded with a lead terminal or the like by thermocompression bonding means, it is best for the composition of the NiCr layer 34 to contain approximately 60% Ni; Ni bonded with
The best composition of the Cr layer 34 is one containing approximately 70% Ni.

Therefore, in Figs. 2 and 3, N.
The target 13 was made of NiCr containing 60% i.
When made with 70% NiCr, the NiCr film for electrodes has excellent thermocompression bonding properties, and the Ni film for electrodes has excellent solderability.
Cr film can be deposited in the same Pelger, and two types of hybrid integrated circuits can be produced in small quantities, one for thermo-compression and one for soldering, or the electrode layer on the front is thermo-compression and the electrode layer on the back is The manufacturing process for hybrid integrated circuits, which requires soldering, is significantly shortened.

(g) As described in detail, according to the present invention, two types of hybrid integrated circuits produced in small quantities are made in the same process, and circuit elements on the front and back sides are made in the same process. The effect of significantly shortening the man-hours and being able to provide the product to users at low cost is significant.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram for explaining the outline of a magnetron sputtering apparatus, FIG. 2 is a schematic diagram for explaining the outline of a magnetron sputtering apparatus according to an embodiment of the present invention, and FIG. 3 is a schematic diagram for explaining the outline of a magnetron sputtering apparatus according to an embodiment of the present invention. FIG. 4 is a schematic cross-sectional view showing an enlarged structure of an electrode layer formed on a thin film hybrid integrated circuit board; FIG. The figure shows NiCr deposited using a magnetron sputtering device.
It is a figure showing the characteristic of an Au electrode layer. In the figure, 1, 11.21 are substrate holders, 2.1
2゜13 is the target, 3.14.15 is the shirt-14
,16,1? , 22.31 is a substrate, 23 is a through hole, 33
34 represents an electrode layer, 34 represents a NiCr layer, and 35 represents an Au layer. Figure 1 Figure 2, Figure 3 Figure 4 Figure 5 (%) iVt / (NL+ Cr)

Claims (2)

[Claims] (1) A substrate is attached to the cylindrical surface of a cylindrical substrate holder that can be rotated or reversed, and a first target for sputtering is provided on the inside of the cylindrical surface, and a sputtering target is provided on the outside of the cylindrical surface. 1. A method for forming a thin film, comprising depositing two types of sputtered films on the substrate in the same bell jar using a second target for forming a thin film. (2) To attach the substrate to the cylindrical surface of the holder, a through hole is opened to expose a predetermined portion of the surface, and sputtering is performed on both the front and back surfaces of the substrate using the first and second targets. A patented thin film forming method characterized by depositing a film. <<3>> The substrates are attached to the inside and outside of the cylindrical surface of the holder, the inner substrate is coated with a sputtering film using the second target, and the outer substrate is coated with a sputtering film using the first target. A method of forming a thin film according to claim 1, characterized in that a sputtering film is deposited.