JP2502581B2 - Method for forming protruding electrode of semiconductor element - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a protruding electrode of a semiconductor element used in electric equipment and the like.

2. Description of the Related Art Each step of the first method of forming a protruding electrode of a conventional semiconductor device will be specifically described with reference to FIGS. First, as shown in FIG. 2A, an electrode 9 made of gold having a thickness of about 50 μm to 100 μm is thermocompression bonded to the tip of a copper foil 10 to be a lead wire. Next, as shown in FIG. 2B, a thermocompression bonding jig 7 is used to thermocompress the gold electrode 9 integrated with the above-mentioned copper foil 10 on the aluminum electrode 5 serving as the electrode extraction portion of the semiconductor element 3, A finished product in which a protruding electrode is formed on the aluminum electrode 5 of the semiconductor element 3 shown in FIG. 2c is obtained. Reference numeral 4 represents a protective layer of the semiconductor element 3.

Next, each step of the second method will be specifically described with reference to FIGS. The same components as those in FIG. 2 are designated by the same reference numerals. First, as shown in FIG. 3A, a chromium layer 11 is formed on the entire surface of the semiconductor element 3 including the aluminum electrode 5 by sputtering. The state where the copper thin film layer 12 is formed by sputtering copper on the chromium layer 11
Shown in Figure b. Next, as shown in FIG.
After spinner 13 is applied and cured on the entire surface, predetermined patterning is performed, and then copper plating is performed to form a copper plating layer 14 for the purpose of thickening the copper layer, as shown in FIG. 3d. Then, as shown in FIG. 3e, the photoresist 13 is removed by etching, and unnecessary portions of the copper foil film 12 and the chromium layer 11 are etched. Solder balls 15 are bonded on the copper plating layer 14 by a flow to obtain a finished product shown in FIG.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the first method, the copper foil 10 serving as the lead wire is not directly in contact with the surface of the semiconductor element 7, and the copper foil 10 and the aluminum electrode 5 are connected via the electrode 9. In order to join, the thickness of the electrode 9 made of gold is required to be about 50 μm to 100 μm, and the cost is very high. In the second method, the process is complicated, and the plating solution, the etching solution, and the like come into contact with the semiconductor element 3, so that the semiconductor element 3 is greatly damaged and the reliability is significantly reduced. In addition, the equipment required in the manufacturing process is a spinner coating machine, an ultraviolet exposure device,
Since there are many expensive equipment such as sputtering equipment and plating equipment, the manufacturing cost is high.

The present invention solves such a conventional problem, and provides a method for forming a protruding electrode for a semiconductor device having a simple structure, low cost, and high reliability.

Means for Solving the Problems A method for forming a bump electrode of a semiconductor device according to the present invention comprises an electrically resistive material in which only a first surface and a second surface facing the first surface are gold-plated. Parts
It is characterized in that the first surface is bonded by thermocompression bonding so as to come into contact with the electrode extraction portion of the semiconductor element.

A member is formed of a material having a large dielectric constant, and gold plating is applied only to the first surface of the member and the second surface opposite to the first surface, thereby forming a capacitor between the gold-plated layers. Then, the first surface is bonded by thermocompression so that the first surface comes into contact with the electrode lead-out portion of the semiconductor element.

Effect According to the method for forming the bump electrode of the semiconductor element of the present invention, since the member whose surface is gold-plated is used as the bump electrode, the gold plating can be thin and the cost is very low. Further, since the protruding electrode is simply bonded to the aluminum electrode portion of the semiconductor element by thermocompression bonding, the semiconductor element is less damaged in the forming method, and the process cost can be reduced by a simple method.

Furthermore, since the member is an electric resistance material, signals can be transmitted and received via a predetermined electric resistance, and if the member is made of a capacitor material, signals can be transmitted and received via a predetermined capacitance. .

Example Hereinafter, each step of one example of the present invention will be described with reference to FIGS.
A detailed description will be given according to f. The same components as those in FIG. 3 are designated by the same reference numerals. The member 8 serving as the nucleus of the bump electrode shown in FIG. 1a is made of an electric resistance material such as ruthenium oxide or a capacitor material having a large relative dielectric constant such as barium titanate, and its shape is the first surface. It is necessary that at least one of the surfaces 8a is flat and has a smaller outer size than the surface of the aluminum electrode 5 of the semiconductor element 3, but other shapes may be arbitrary.

Only the first surface 8a of the member 8 and the second surface 8b opposite to the first surface 8a are plated with gold 2 as shown in FIG. 1b. Thereafter, the member 8 having the gold plating layer 2 formed thereon is thermocompression bonded onto the aluminum electrode 5 of the semiconductor element 3, and after the thermocompression bonding, the metal mask 6 is removed to remove the aluminum electrode 5 of the semiconductor element 3 as shown in FIG. A finished product with a protruding electrode formed on it is obtained. In the case of this embodiment, if the member 8 is an electric resistance material, signals are transmitted and received via a predetermined electric resistance, and if the member 8 is a capacitor material,
Signals can be sent and received via a predetermined capacity.

EFFECTS OF THE INVENTION As described above, in the method of forming a protruding electrode of a semiconductor element of the present invention, a member having only two surfaces facing each other with gold plating is thermocompression-bonded to an electrode mounting portion on the surface of the semiconductor element to join the members.
This is a method of forming a protruding electrode of a semiconductor element.Since the surface of the member is plated with gold to form a protruding electrode, the thickness of the gold plating can be thin and the cost is significantly low. Reliability is also improved due to only heat and some pressure. Further, since the protruding electrode itself has a function of a capacitor or a resistor, it is highly practical and extremely useful.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a method of forming a protruding electrode of a semiconductor device according to an embodiment of the present invention in the order of steps, and FIG. 2 is a side sectional view showing a method of forming a protruding electrode of a conventional semiconductor element in the order of steps. The drawings are side cross-sectional views showing another conventional method of forming protruding electrodes of a semiconductor element in the order of steps. 2 ... gold-plated layer, 3 ... semiconductor element, 4 ... protective layer,
5 ... Aluminum electrode, 8 ... Material.

Claims (2)

(57) [Claims] 1. A member made of an electric resistance material, each of which is gold-plated only on a first surface and a second surface facing the first surface, wherein the first surface is an electrode lead-out portion of a semiconductor element. A method for forming a protruding electrode for a semiconductor element, which comprises thermocompression bonding so as to come into contact with the bonding. 2. A gold-plated layer is formed by forming a member with a material having a large dielectric constant, and subjecting only a first surface of the member and a second surface facing the first surface to gold plating. And forming a capacitor by thermocompression bonding so that the first surface is in contact with the electrode lead-out portion of the semiconductor element.