JPH0536781A - Burn-in method and apparatus - Google Patents

Abstract

PURPOSE:To control the temperature of a plurality of semiconductor chips themselves with good accuracy and nearly uniformly by a method wherein temperature sensors are installed at individual semiconductor devices in the semiconductor chips at the inside of the semiconductor devices, they are monitored and ventilation amounts are set at individual ventilation ports according to monitored results. CONSTITUTION:A plurality of burn-in boards 1 are installed at the inside of a burn-in (high-temperature continuous operation) test container 6; semiconductor devices which are provided with semiconductor chips 71 to 73 at the inside are set on the boards. Integrated circuits 711 to 713 and diodes 721 to 723 for temperature detection use are formed on the semiconductor chips 71 to 73. The electric characteristic of the diodes 72 for temperature detection use is monitored individually by using a temperature detector 92. A control device 93 controls an electricity-feeding amount by using an electricity-feeding device 91 and a ventilation amount from ventilation ports 83a to 83c via wind-amount control parts 82a to 82c on the basis of monitored results by the temperature detector 92. Thereby, the temperature of the semiconductor chips themselves can be controlled with good accuracy and uniformly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a burn-in method and apparatus, and more particularly to a burn-in (high temperature continuous operation) test in which a semiconductor device as a device under test is subjected to a temperature load and an electric load.

[0002]

2. Description of the Related Art A burn-in test is essential for predicting the life of semiconductor devices and detecting early failures in the screening process. Generally, the burn-in test is performed as follows. FIG. 6 is a perspective view of the burn-in board 1. A plurality of sockets 3 in which semiconductor devices (not shown) to be tested are set are provided on a board 2 made of heat-resistant resin or the like, and one end of the board 2 has an external terminal for making electrical contact with the outside. 4 are provided.
At the other end of the board 2, a handle 5 is provided for an operator to operate the burn-in board 1. The terminals (not shown) of the socket 3 and the external terminals 4 are connected by the wiring (only part of which is shown) on the board 2.

Such a burn-in board 1 is set in a burn-in test container 6 as shown in FIG. That is, the burn-in test container 6 includes a housing 61, which is a main body, and a lid 6
2 has a structure in which they are connected by a hinge mechanism 63, and an insertion slit 65 of a board connector 64 provided inside
Burn-in board 1 is inserted in. As a result, the external terminal 4 of the burn-in board 1 and the terminal (not shown) of the board connector 64 are connected. Through this connection, the semiconductor device is energized by an unillustrated energizing device. Although not shown, the burn-in test container 6 is provided with a temperature adjusting device, and usually has a structure in which hot air is supplied into the burn-in test container 6 or a heater is provided.

It should be noted that the internal temperature of the burn-in test container 6, that is, the environmental temperature T of the semiconductor device which is the device under test.
_“A” is measured by a temperature sensor provided near the inner wall of the housing 61. The burn-in test is conventionally performed by monitoring the measured temperature and controlling the temperature adjusting device.

[0005]

However, in the above-mentioned prior art, the burn-in test could not be suitably performed for the following reasons. That is, it is the environmental temperature T of the device under test that can be monitored in real time by the conventional technique.
_a , which is the surface temperature of the semiconductor chip, especially p
It does not match the junction temperature T _{j at the} n-junction portion or the Schottky junction portion. Since the failure of the semiconductor device depends on the junction temperature T _j , conventionally, the junction temperature T _j is estimated from the result of measuring the environmental temperature Ta and the burn-in test is performed. However, this examine the relationship between the environmental temperature T _a and the junction temperature T _j requires a very complicated task, the size of semiconductor devices, formats, such as specifications require a separate estimated work each time different. Therefore, it is difficult to perform a simple and accurate burn-in test. Also,
Since the environmental temperature T _a differs depending on the position in the test container 6 and the heat generation amount of each semiconductor device is not the same, it is not easy to screen a large number of devices under the same conditions.

Therefore, an object of the present invention is to provide a burn-in method and apparatus capable of accurately controlling the temperature of the chip itself in a plurality of devices under test to which a burn-in test is simultaneously performed.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a plurality of semiconductor devices, each having a semiconductor chip as a device under test, are placed in an environment of a predetermined temperature in a test container having a plurality of air vents. In the burn-in method of conducting a test by energizing chips, a temperature sensor is formed in advance on each of a plurality of semiconductor chips,
The temperature of multiple semiconductor chips is measured by detecting the electrical characteristics of multiple temperature sensors during the test, and based on the temperature measurement results, the temperature of multiple semiconductor devices is made approximately the same at multiple air outlets. The feature is that the air volume is controlled independently.

Further, according to the present invention, a plurality of semiconductor devices as semiconductor devices to be tested having a semiconductor chip therein and accommodating a plurality of blowing ports, and an amount of air blown into the inside of the test container are set to predetermined values. In the burn-in device provided with the temperature adjusting means for adjusting to, and the energizing means for supplying electric power to the plurality of semiconductor chips, by detecting the electrical characteristics of the temperature sensor formed in advance in each of the plurality of semiconductor chips during the test. The measuring means for measuring the temperature of each of the plurality of semiconductor chips, and based on the output of the measuring means, the temperature control means is controlled so that the temperatures of the plurality of semiconductor chips become substantially the same, And a control means for independently setting the air flow rate.

[0009]

According to the burn-in method of the present invention, the temperature sensor is provided for each device on the semiconductor chip itself inside the semiconductor device, the temperature sensor is monitored, and the air blowing amount is set for each air blowing port according to the result. Therefore, the temperatures of the plurality of semiconductor chips themselves can be accurately and substantially uniformly controlled.

Further, in the burn-in device of the present invention, the temperature sensor provided on the semiconductor chip is monitored by the measuring means, and the temperature adjusting means is controlled based on the result to set the air volumes at the plurality of air outlets. Therefore, by setting a program for controlling the temperature uniformly in the control means, it is possible to automatically and accurately control the temperature substantially uniformly.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a conceptual diagram of an air blowing system of a burn-in system according to an embodiment, and FIG. 2 is a conceptual diagram of a temperature detecting and energizing system. A plurality of burn-in boards 1 are provided inside the burn-in test container 6, and semiconductor chips 7 ₁
Semiconductor device having a to 7 ₃ therein (not shown) is set by the socket 3 ₁ to 3 _3, for detecting temperature of the temperature sensor and the integrated circuit 71 ₁ to 71 ₃ in the semiconductor chip ₇₁ to 7 ₃ Diodes 72 _{1 to} 72 ₃ are formed. The burn-in test container 6 is provided with a blower 81 as a temperature adjusting device and air volume control units 82a to 82c so that hot air is supplied. An electric load is applied to the integrated circuit 71 of the semiconductor chip 7 independently of the energization device 91, and the electric characteristics (especially the change of the rising voltage V _F ) of the temperature detecting diode 72 are individually detected by the temperature detector 92. The junction temperature T _j is measured for each device.

Based on the monitoring result of the temperature detector 92, the control device 93 determines the amount of electricity supplied by the electricity supply device 91 and the air outlet 83.
The amount of air blown from a to 83c is controlled via the air volume control units 82a to 82c. The air volume control is performed by the control plates 84a to 84c provided on the air blowing ports 83a to 83c.
It is made by driving. Further, the allowable range of the junction temperature T _j in the burn-in test is stored in the control device 93, and is programmed in advance to control the energization device 91 and the temperature adjusting device in comparison with the monitor result.

FIG. 3 shows the semiconductor chip 7 in the above embodiment.
And the IV characteristic of the temperature detecting diode 72 (see FIG. 11B).
As shown, an integrated circuit 71 and a temperature detection diode 72 are formed on the semiconductor chip 7, and the integrated circuit 71
A current-carrying pad 73 connected to and a monitoring pad 74 connected to the anode and cathode of the temperature detecting diode 72 are provided. Such a semiconductor chip 7 is packaged as a flat package or a leadless chip carrier (LCC) to form a semiconductor device as a device under test. Such temperature monitoring in the semiconductor chip 7 is performed by observing the IV characteristic of the temperature detecting diode 72. That is, since the rising voltage V _F of the IV characteristic shown in FIG. 2A changes linearly with temperature, the change in the rising voltage V _F causes the junction temperature T _F to change.
_j can be accurately determined.

4 and 5 show a semiconductor device 7 which is a device under test in the burn-in apparatus of the above embodiment.
0 is mounted on the socket 3, FIG. 3 is a perspective view, and FIG. 4 is a sectional view. The socket 3 has a base 31 and a lid 32, which are openably and closably coupled by a hinge 33 and closed by engagement of a lever 34 and a hook 35. When the through hole 36 is formed in the central portion of the base 31, a cross-shaped recess 37 is formed from the upper surface, and the terminal 38 is provided therein. Then, one end of the terminal 38 has the base 31
Of the burn-in board 1 and is connected to the wiring on the burn-in board 1. Further, in the central portion of the lid 32, the heat dissipation member 39
Is screwed on. On the other hand, a terminal 76 is provided on the bottom surface of the semiconductor device 70, and when mounted on the socket 3, the terminal 76 contacts the terminal 38 of the socket 3. When the semiconductor device 70 is mounted in the recess 37 and the lid 32 is closed, the bottom surface of the heat dissipation member 39 contacts the top surface of the semiconductor device 70, and heat dissipation is achieved.

According to the above embodiment, the temperature of the semiconductor chip 7 itself can be monitored with extremely high accuracy for any of the plurality of chips. That is, the temperature of the semiconductor chip 7 itself is not only dependent on the different environmental temperature T _a by the position of the internal test apparatus is also dependent on the heat dissipation of the heating and the external in the integrated circuit 71, the heating value and heat radiation amount Has a large variation due to the mounting condition. However,
In this embodiment, since the junction temperatures T _j of the temperature detecting diodes 72 provided on the semiconductor chips 7 are individually monitored, the temperatures of all the semiconductor chips 7 can be directly measured.

Therefore, by using this monitoring result, the air volumes at the plurality of air outlets 83a to 83c can be calculated as follows.
The surface temperature (junction temperature T _j ) of the entire semiconductor chip 7 can be controlled accurately and uniformly by controlling independently. That is, the temperature is made uniform by differentiating the air flow rate between the portion having many devices having high temperature and the portion having many devices having low temperature. Specifically, the air volume may be increased when there is a high-temperature device, and may be returned to the air volume for steady operation when the temperature falls to an appropriate value. As a result, it is possible to realize the accuracy of screening and the improvement of the yield at the same time.

For example, in a semiconductor device generating heat of 50 W, when the temperature resistance θ _ja = 2 ° C./W, the junction temperature Tj = 150 ° C., the ambient temperature T _a = 50.
It may be set to ° C. And the temperature of another device is 1
When the temperature reaches 60 ° C., the air flow here is increased, and when the temperature returns to 150 ° C., the air flow may be set to a steady air flow.

The temperature sensor according to the present invention is not limited to the temperature detecting diode formed on the semiconductor chip separately from the integrated circuit 71, but a diode inside the integrated circuit may be used, or as a transistor. Good. Also, a NiCr-based metal thin film resistor may be formed on the semiconductor chip. Furthermore, various modes can be adopted for the number of air outlets and a specific air volume control mechanism.

[0020]

As described above, according to the burn-in method of the present invention, the temperature sensor is provided on the semiconductor chip itself inside the semiconductor device, the temperature sensor is monitored, and the air volume is set for each of the plurality of air outlets. Therefore, the temperature of the semiconductor chip itself can be accurately and uniformly controlled. Therefore, it is possible to perform a burn-in test with high yield and with high accuracy.

Further, in the burn-in device of the present invention, the temperature sensor provided in each of the plurality of semiconductor chips is monitored by the measuring means, and the temperature adjusting means is controlled based on the result, and the air flow rate from the plurality of air outlets is controlled. Are adjusted individually. Therefore, by setting a temperature control program in the control means, it is possible to automatically and uniformly control the temperature.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of an air blowing system of a burn-in device according to an embodiment.

FIG. 2 is a conceptual diagram of a temperature measurement and energization system of a burn-in device according to an example.

FIG. 3 is a diagram showing a configuration of a semiconductor chip 7 and characteristics of a temperature detecting diode 72 in the example.

FIG. 4 is a perspective view of the socket 3 in the embodiment.

FIG. 5 is a cross-sectional view of the socket 3 in the embodiment.

FIG. 6 is a perspective view showing a configuration of a burn-in board 1.

FIG. 7 is a perspective view of a burn-in test container 6.

[Explanation of symbols]

1 ... Burn-in board 2 ... Board 3 ... Socket 31 ... Base 32 ... Lid 34 ... lever 35 ... Hook 38 ... Terminal 39 ... Heat dissipation member 6 ... Burn-in test container 7 ... Semiconductor chip 70 ... Semiconductor device 71 ... Integrated circuit 72 ... Diode for temperature detection 81 ... Blower 82 ... Air volume control unit 83 ... Blower 84 ... Air volume control plate 91 ... energizing device 92 ... Temperature detector 93 ... Control device

Claims (2)

[Claims] 1. A test is carried out by placing a plurality of semiconductor devices as devices under test having semiconductor chips therein in an environment of a predetermined temperature in a test container having a plurality of air blowing ports and energizing the plurality of semiconductor chips. In the burn-in method, the temperature sensor is formed in advance on each of the plurality of semiconductor chips, and the temperature of each of the plurality of semiconductor chips is measured by detecting the electrical characteristics of the plurality of temperature sensors during the test. The burn-in method is characterized in that, based on the measurement result of the temperature, the air volumes at the plurality of air outlets are independently controlled so that the temperatures of the plurality of semiconductor devices become substantially the same. 2. A test container having a plurality of semiconductor devices as a device under test having a semiconductor chip therein and having a plurality of air blowing ports, and a temperature for adjusting the amount of air blown into the test container to a predetermined value. In a burn-in device provided with an adjusting means and an energizing means for supplying electric power to the plurality of semiconductor chips, by detecting during a test the electrical characteristics of temperature sensors formed in advance in each of the plurality of semiconductor chips, Measuring means for measuring the temperature of each of the plurality of semiconductor chips, and based on the output of the measuring means, the temperature control means is controlled so that the temperatures of the plurality of semiconductor chips are substantially the same from the plurality of air outlets. And a control means for independently setting the air flow rate of the burn-in device.