JPH0611348U - Coating agent coating device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a coating agent coating device which can semi-automatically coat a coating agent and accurately store it within a predetermined coating range. [Structure] The tip 11a of the guide plate 11 is the semiconductor substrate 2
Since the coating agent 7 is applied to the surface of the semiconductor substrate 2 while being slidably contacted with the concave portion 13, the coating agent 7 can be accurately applied only to a predetermined portion. Therefore, the coating agent 7 is not applied onto the bevel groove 4, and the coating agent 7 is applied semi-automatically, so that the work efficiency is improved.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a coating agent coating device for coating a coating agent only on a necessary portion of the surface of a semiconductor pellet.

[0002]

[Prior art]

 As a semiconductor device for high power, for example, there is a thyristor having a structure as shown in FIGS. In these figures, a semiconductor substrate 2 having a thyristor structure is fixed to the upper surface of the temperature compensating plate 1. The outer peripheral surface of the semiconductor substrate 2 is provided with a bevel process 3 for increasing the breakdown voltage. Further, a bevel groove 4 is formed on the inner side of the bevel groove 4 in order to increase the breakdown voltage of the P2-N1 joint. A control electrode 5 is provided in the center of the semiconductor substrate 2, and a cathode electrode 6 is provided outside the control electrode 5. Further, in the semiconductor substrate 2, a PN junction portion having a thyristor structure composed of P1, N1, P2 and N2 layers as shown in FIG. 6 is formed.

FIG. 6 is a partial cross-sectional view showing the process of manufacturing the semiconductor pellet. In the figure, a semiconductor substrate 2 is fixed to the temperature compensating plate 1, and a cathode electrode 6 and a control electrode (not shown) are already formed on the surface of the semiconductor substrate 2. Further, in order to increase the pressure resistance of the semiconductor pellet, the outermost periphery of the semiconductor pellet is beveled 3 and a bevel groove 4 is formed inside thereof. Further, in the next step, mechanically damaged portions of the both bevel surfaces are removed by chemical etching and the surfaces are cleaned, but prior to this, chemical etching is performed on the inner side in the radial direction of the bevel groove 4 of the semiconductor substrate 2. The coating agent 7 is applied so as not to come off. Next, the exposed portion of the semiconductor substrate 2 is chemically etched, and then an insulating material is applied to both bevel surfaces, after which the coating agent 7 is peeled off and an upper electrode (not shown) is arranged.

By the way, as shown in FIG. 6, the coating agent 7 is applied to the entire surface inside the bevel groove 4 so as not to be chemically etched. As a coating method, a liquid coating agent 7 is conventionally used. It is painted or is applied using a syringe or the like. In such a case, the application condition is that the application range of the coating agent 7 does not extend above the bevel groove 4 and that the cathode electrode 6 is all coated. After the coating agent 7 is applied, the temperature of the entire semiconductor pellets is raised and left for a predetermined time in order to cure the coating agent 7.

[0005]

[Problems to be solved by the device]

 In the conventional coating agent application method using a brush or a syringe, it is necessary to pay close attention so that the coating agent does not reach the bevel groove 4 and to ensure that the cathode electrode 6 is completely covered. However, there was a problem to be solved that it was necessary to do it manually and the work efficiency did not increase.

[0006]

[The purpose of the device]

 The present invention has been made in order to solve the above problems, and a coating agent coating device capable of semi-automating the coating of a coating agent on the surface of a semiconductor substrate and accurately storing the coating agent within a predetermined range. It is intended to provide.

[0007]

[Means for solving problems]

 The coating agent coating device of the present invention comprises a rotary pedestal on which a semiconductor pellet is placed, a guide plate located above the semiconductor pellets placed on the rotary pedestal, and a coat supported by the guide plate. And a tip of the guide plate is in sliding contact with a recess formed on the outer periphery of the semiconductor substrate of the semiconductor pellet, and the rotary pedestal is rotated to apply the coating agent from the coat injection needle to the semiconductor substrate. The feature is that it is applied only to a predetermined portion of the surface.

[0008]

[Action]

 In the coating agent applying device of the present invention, the tip of the guide plate is brought into sliding contact with the concave portion of the semiconductor substrate, and the rotary pedestal is rotated to apply the coating agent to the surface of the semiconductor substrate. Only the coating agent can be applied accurately. Therefore, the coating agent is not applied to the bevel groove, and the coating agent is applied semi-automatically, which improves the work efficiency.

[0009]

【Example】

 Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2. In these figures, the coating agent coating device 8 is provided with a rotary pedestal 9, and the semiconductor pellet 10 is placed on the rotary pedestal 9. A guide plate 11 is provided above the semiconductor pellets 10, and a coating agent injection needle 12 is fixed to the tip of the guide plate 11. The guide plate 11 is supported by columns (not shown), and as shown in FIG. 1, is structured to be movable in the Y direction (vertical direction) and the X direction (radial direction) with respect to the semiconductor pellet 10. Further, when the tip portion 11a of the guide plate 11 is in sliding contact with the concave portion 13 of the semiconductor pellet 10, the spring force of the coil spring is applied in both the X direction and the Y direction so as to be repulsed. Although not shown, one end of the coating agent injection needle 12 is configured to follow the movement of the guide plate 11 and is connected to a coating agent storage container via a soft tube.

Next, the operation of the coating agent coating device 8 configured as described above will be described. First, as shown in FIG. 2, the semiconductor pellets 10 are placed on the rotary pedestal 9. Next, as shown in FIG. 1, the tip portion 11a of the guide plate 11 is brought into sliding contact with the recess 13 on the outer periphery of the semiconductor pellet 10. Next, the rotary pedestal 9 is rotated at a low speed of about 10 revolutions per minute. Next, the coating agent is guided from the storage container (not shown) to the tip of the coating agent injection needle 12 and allowed to flow into the recess 13. When the guide plate 11 makes one round around the outer periphery of the semiconductor pellet 10 by the rotation of the rotary pedestal 9, the coating agent 7 is applied from the recess 13 to a predetermined portion inside the radial direction, so that the guide plate 11 is moved upward. Let

Next, since the coating agent 7 is applied to the central portion of the semiconductor pellet 10, the coating agent 7 is applied to the non-applied portion with a brush. In this case, the brush coating is applied only to the central portion away from the bevel groove 4, so that a great deal of attention is not required. FIG. 3 shows the semiconductor pellet 10 on which the coating agent 7 has been applied in this manner. The reason for applying the coating agent 7 by rotating the tip 11a of the guide plate 11 while sliding the tip 11a of the guide plate 11 into the recess 13 formed on the outer periphery of the semiconductor pellet 10 is as follows. That is, even if the center position of the temperature compensating plate 1 and the center position of the cathode or gate pattern on the upper surface of the semiconductor pellet 10 are slightly eccentric, the guide plate 11 is pressed in the X direction by the spring force of the coil spring. This is because the coating agent injection needle 12 follows the recess 13 so that the coating agent 7 is applied inside the recess 13 and the coating agent 7 is not applied onto the bevel groove 4.

[0012]

[Effect of device]

 As described above, according to the coating agent application device of the present invention, the coating agent is not applied on the bevel groove, and the application of the coating agent is performed semi-automatically, so that the work efficiency is improved. Has the effect of.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an outline of a coating agent coating device of the present invention.

FIG. 2 is an explanatory view showing an outline of the coating agent applying apparatus.

FIG. 3 is a partial cross-sectional view of a semiconductor pellet after applying a coating agent using the coating agent application device.

FIG. 4 is a plan view of a semiconductor pellet.

FIG. 5 is a cross-sectional view taken along line AA of the semiconductor pellet.

FIG. 6 is a partial cross-sectional view of a state in which a coating agent is applied to the semiconductor pellets using a conventional coating agent application device.

[Explanation of symbols]

 1 Temperature Compensation Plate 2 Semiconductor Substrate 3 Bevel Processing 4 Bevel Groove 5 Control Electrode 6 Cathode Electrode 7 Coating Agent 8 Coating Agent Application Device 9 Rotating Stand 10 Semiconductor Pellet 11 Guide Plate 12 Coating Agent Injection Needle 13 Recess

Claims (1)

[Scope of utility model registration request] 1. A rotary pedestal for mounting a semiconductor pellet,
The semiconductor substrate has a guide plate positioned above the semiconductor pellet mounted on the rotary pedestal and a coating agent injection needle supported by the guide plate, and the tip of the guide plate is a semiconductor substrate of the semiconductor pellet. A coating agent coating device, which is in sliding contact with a concave portion formed on the outer periphery, and rotates the rotary support to apply a coating agent from a coating injection needle only to a predetermined portion of the surface of the semiconductor substrate.