JPS62293738A - Semiconductor device - Google Patents

Abstract

PURPOSE:To equalize current shares in each finger section by forming a cathode electrode metal and a gate electrode metal to a symmetric pattern shape so that distances among respective finger section and the connecting sections of leads lead out of the upper sections of the cathode electrode metal and the gate electrode metal are all made uniform CONSTITUTION:The pattern shapes of electrode metals are formed symmetrically so that distances reaching the noses K1, K2..., and G1, G2... of each finger section in respective cathode region and gate region from the connecting sections 4a, 5a of a cathode lead 4 and a gate lead 5 are equalized. Consequently, lateral resistance R and reactance among cathode finger sections for respective GTO1, GTO2... and the connecting section 4a of the cathode lead 4 and lateral resistance R and reactance L among gate finger sections and the connecting section 5a of the gate lead 5 are all made uniform. Accordingly, the current shares of each finger section are equalized, thus uniformly operating respective finger section.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a semiconductor device, and in particular, to a gate turn off thyristor (hereinafter abbreviated as GTO). The present invention relates to a semiconductor device having an electrode structure that can improve φ-on and gate turn-off characteristics.

[Prior Art] FIGS. 3 and 4 show an example of an electrode metal lead-out structure of a GTO.

In these figures, four layers of Pc-Na-PR-NE are formed on a semiconductor substrate 1 forming a GTO, a cathode electrode metal 2 is provided on the NE layer of this semiconductor substrate 1, and 28 layers are formed. A gate electrode metal 3 is provided on top.

These cathodes 1! Pole metal 2 and gate electrode metal 3
is a plurality of finger portions 2a that intertwine with each other in a comb-like shape according to the pattern shapes of the NE layer and the 28th layer immediately below;
3a.

The surfaces of the above cathode electrode metal 2 and gate electrode metal 3"
Cando lead wires 4 and gate lead wires 5 are respectively drawn out from the core of the main body by wire bonding or the like.

[Problems to be Solved by the Invention] In a GTO having the above-mentioned electrode metal lead-out structure, by biasing the gate negatively, the gate
When turning off, there are the following problems.

That is, the current flowing through each finger portion of the cathode region and the gate region is transferred to the connecting portion 4a of the cathode lead wire 4 and the gate lead wire 5, which are drawn out from each portion of the electrode metal 2.3 on the cathode region and the gate region.
, 5a differs due to the difference in pattern shape, and the lateral resistance and reactance between them are different, so they are not equal.

For example, in the electrode metal pattern shown in FIG. 3 above, the cathode current is at a maximum near the connection part 4a of the cathode lead wire 4, and decreases in proportion to the distance from the connection part 4a of the cathode lead wire 4. . In other words, K >
K 2 > K +.

Further, the gate current also becomes maximum at G3 near the connection portion 5a of the gate lead wire 5, and decreases in proportion to the distance from the connection portion 5a of the gate lead wire 5. That is, G3>
Since G2 > Gl, there is a problem in that the current distribution is not uniform, and therefore, each finger section cannot operate uniformly.

[Purpose of the Invention] This invention was made to solve the above-mentioned problems, and the current distribution among the finger parts becomes uniform, each finger part can operate uniformly, and the gate Φ turn fist is turned on. Another object of the present invention is to provide a semiconductor device that can improve gate turn-off characteristics.

[Means for Solving the Problems] In the semiconductor device according to the present invention, the cathode electrode is connected so that the distances between each finger portion and the connection portion of the lead wire drawn out from the cathode electrode metal and the gate electrode metal are all equal. The metal and the gate electrode metal are formed in a symmetrical pattern. [Function] In the semiconductor device of the present invention, the lateral resistance and reactance in each finger portion are equal, and the current distribution in each finger portion is uniform. become.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1(A) is a schematic diagram schematically showing the pattern shape of the extraction electrode structure in the semiconductor device of the present invention, and FIG.
B) is an equivalent circuit diagram when the electrode structure has the above pattern shape.

In this invention, from the connecting portions 4a and 5a of the cathode lead wire 4 and gate lead wire 5 to the tips of the respective finger portions of the cathode region and the gate region, + and 2 are connected.
, ni3, ni4...and Gl+G2 1
The pattern shape of the electrode metal is formed symmetrically so that the distances to G3, GA, . . . - are equal.

Therefore, as shown in the same figure (B), each GTO
I, Cathode finger part of GTO2, GTO3... Lateral resistance R and reactance between 1 and connection part 4a of cathode lead wire 4, Lateral resistance between gate finger part and connection part 5a of gate lead &Ia5 R and reactance L are all equal.

FIG. 2 is a plan view showing the actual pattern shape of the electrode metal, which is formed in a stepwise symmetrical shape so that the cathode electrode metal 2 and the gate electrode metal 3 are integrally connected at the outermost side. .

As described above, in the present invention, the electrode metal is patterned so that the distances from the connecting parts 4a and 5a of the cathode lead wire 4 and the gate lead wire 5 to the tips of the finger parts of the respective cathode and gate regions are equal. Since the shape is formed symmetrically, the current distribution in each finger portion is uniform.

[Effects of the Invention] As is clear from the above description, according to the present invention, the distance between each finger portion and the connection portion of the lead wire drawn out from the cathode electrode metal and the gate electrode metal is all Since the cathode electrode metal and the gate electrode metal are formed in a symmetrical pattern shape so that they are equal, the current distribution in each finger part is uniform, and therefore each finger part can operate uniformly, and the GTO gate turn-on and It has excellent effects such as improving gate turn-off characteristics.

[Brief explanation of the drawing]

FIG. 1(A) is a schematic diagram schematically showing the pattern shape of the extraction electrode structure in the semiconductor device of the present invention, and FIG.
B) is an equivalent circuit diagram when the electrode structure has the above pattern shape, FIG. 2 is a plan view showing the actual pattern shape of the electrode metal of the present invention, and FIGS. 3 and 4 are diagrams of the conventional semiconductor. FIG. 3 is a plan view and a cross-sectional view showing the extraction electrode structure of the device. 2... Cathode electrode metal, 3... Gate electrode metal, 4... Cathode lead wire, 4a, 5a... Connection portion, 5... Gate lead wire.

Claims (1)

[Claims] It has a plurality of finger parts, a cathode region and a gate region are intertwined with each other in a comb-like shape, and a cathode electrode metal and a gate electrode metal are respectively provided on the cathode region and the gate region, and the cathode electrode metal and gate electrode In a semiconductor device having a structure in which lead wires are drawn out from above the metal, the distances between each of the finger parts and the connection parts of the lead wires drawn out from the cathode electrode metal and the gate electrode metal are all equal. A semiconductor device characterized in that the cathode electrode metal and the gate electrode metal are formed in a symmetrical pattern shape.