JP2947489B2 - Temperature compensation method for IC test equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

This invention exposes an IC under test to a desired temperature, tests whether the IC normally operates at that temperature, and replaces a guide rail according to the type of IC. IC with change kit that can be used
The present invention relates to a temperature correction method for a test apparatus.

[0002]

2. Description of the Related Art Conventionally, an IC under test is put into a thermostat,
The IC under test is exposed to a desired temperature in a thermostat, and it is tested whether the IC under test operates normally in a desired temperature environment. On the other hand, there are various types of lead-out structures in ICs, and IC types are classified according to the types of terminals. For this purpose, the IC test apparatus uses a guide rail for pouring the IC under test into the thermostat, a guide rail in the thermostat, a guide rail for discharging the IC from the thermostat, and an IC discharged from the thermostat. The guide rails are classified so that they can be exchanged for non-defective products and non-defective ones, and all of the guide rails in the storage portion can be replaced. These interchangeable guide rails are called change kits and are available for ZIP, SO
For J300 (300 is a numerical value representing the terminal interval in mils), for SOJ350, for SOJ400, SOP37
5, SOP450, SOP525, SOP675, DI
P300, DIP400, DIP600, PLCC30
For 0, etc. are prepared.

[0003]

When these various change kits are mounted, there is a disadvantage that the temperature distribution in the thermostat changes. That is, each change kit has a plurality of guide rails, for example, eight guide rails,
For example, two test sockets are prepared for each of the eight guide rails in the thermostat. Therefore, two ICs to be tested are allowed to flow simultaneously for each guide rail, and a total of 16 ICs are allowed to flow simultaneously in parallel, so that 16 ICs can be tested simultaneously.

[0004] When a plurality of ICs are tested at the same time, each IC must be in an environment within an allowable temperature range. Even if the temperature of the heater is controlled so that this condition is satisfied in a state where a certain change kit is mounted, the condition is broken again when the heater is replaced with another change kit.

Therefore, conventionally, a correction value for controlling the temperature of the heater is determined so that the temperature distribution in the constant temperature bath falls within a predetermined temperature range with each change kit mounted, and the correction value is used for the IC. Has been tested. In this manner, the work of obtaining the temperature correction value of the constant temperature bath for each change kit is performed by installing each change kit and changing the temperature of the constant temperature bath from the operating temperature range of −30 ° C. to + 125 ° C. Has the disadvantage that it takes time and effort.

In addition, conventionally, when a change kit having a new structure is manufactured, the temperature correction value must be measured and measured while the change kit is mounted. In addition, the user has to carry out a work of obtaining a temperature correction value by installing a new type of change kit. SUMMARY OF THE INVENTION An object of the present invention is to simplify an operation of obtaining a temperature correction value for keeping a temperature distribution in a constant temperature chamber within an allowable range in an IC test apparatus capable of testing an IC using various types of change kits. It proposes a temperature correction method that can be performed.

[0007]

According to the present invention, there is provided a thermostat, in which the IC under test is operated in the thermostat to determine whether or not the operation of the IC under test is normal.
In an IC test apparatus having a change kit in which guide rails for guiding the IC under test are interchangeably mounted in accordance with the type of the terminal of C, the IC under test is mounted with the reference change kit mounted. The temperature distribution at each test position is measured, and a correction value for correcting the temperature distribution within the allowable range is obtained for each temperature within the operating temperature range, and this correction value is used as a unit-specific temperature correction value. With the temperature corrected using this unit-specific temperature correction value, the temperature distribution characteristics of other types of change kits are obtained, and this temperature distribution characteristic is used as a change kit-specific temperature correction value. A temperature correction method for an IC test apparatus that performs an actual IC test apparatus based on a combined value with a change kit-specific temperature correction value is proposed.

According to the temperature correction method of the present invention, a certain kind of change kit is set as a reference, a temperature correction value is obtained with the change kit set as the reference, and the temperature correction value is determined for each IC test. Determined as the unit-specific correction value of the device. With respect to each IC test apparatus, shipment can be performed only by obtaining the unit-specific correction value. That is, for other change kits, a change kit specific temperature correction value is obtained in advance for each change kit. The change kit specific temperature correction value is obtained by mounting the change kit to be measured on the IC test apparatus in a state where the temperature of the IC test apparatus is corrected by the unit specific temperature correction value.
The temperature of the constant temperature bath of the test apparatus is changed over the entire operating temperature range, and the temperature of the heater is corrected and determined so that the temperature distribution in the constant temperature bath falls within the allowable range for each temperature.

The change kit specific temperature correction value obtained in this manner is the same value between the same type of change kit, but different between the other types of change kit. Therefore, the change kit specific temperature correction value is measured in advance, and the change kit specific temperature correction value is stored in the storage of each IC test apparatus. When the IC is tested, the change kit specific temperature of each type stored in this storage is stored. The correction value is selected and read, and the read change kit specific temperature correction value and the unit specific temperature correction value are combined to correct the temperature. Can be kept within an allowable range.

After all, according to the present invention, if a change kit specific temperature correction value is measured in advance for each change kit type, the change kit specific temperature correction value can be used in any IC test apparatus. . Therefore, at the time of shipment, simply find the unit-specific temperature correction value of the IC test equipment,
Temperature compensation can be applied to all change kits.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS RF shown in FIG. 1 is an example of a unit-specific temperature correction value. The horizontal axis T ° C. indicates the measured temperature, and the vertical axis Y indicates the correction value.
At the horizontal axis T ° C., in this embodiment, the operating temperature range is −
30 ° C. to + 125 ° C., and within this operating temperature range, the measurement points of the temperature distribution in the thermostat are -30 ° C., 0 ° C.,
8, 25 ° C, 50 ° C, 75 ° C, 100 ° C, 125 ° C
The following shows the case where a point is selected. In order to obtain this unit-specific temperature correction value, for example, the temperature distribution in the thermostat, that is, the position of each socket where the IC under test is tested at each measurement temperature with the change kit for ZIP attached to the IC test apparatus. The temperature distribution is measured.

When the temperature distribution is within a predetermined temperature range of 100 ° C. ± 3 ° C. when the heater is at a predetermined temperature, for example, 100 ° C., the correction value is set to 0. Heater temperature is 1
When the average value of the temperature distribution is, for example, 95 ° C. in the state of 00 ° C., when the temperature of the heater must be controlled to 105 ° C. to make the average value of the temperature distribution 100 ° C., the correction value is set to +5.

When the heater temperature is 100 ° C. and the average value of the temperature distribution is, for example, 105 ° C., the average value of the temperature distribution is 100 ° C.
When the heater temperature must be set to 95 ° C. in order to set the correction value, the correction value is set to −5. In this way, a correction value is obtained for each IC test apparatus with the ZIP change kit attached for each temperature within the operating temperature range, and this correction value is used as a unit-specific temperature correction value specific to each IC test apparatus. Each IC
Store in the memory of the test equipment.

CH shown in FIG. 2 is other than ZIP, for example, S
The specific temperature correction value of the change kit for OJ300 is shown. This change kit specific temperature correction value may be measured by any IC test apparatus as long as the IC test apparatus has been corrected by the previously obtained unit specific temperature correction value. That is,
By applying a correction using the unit-specific temperature correction value,
In any IC test apparatus, the temperature distribution in the IC test apparatus in the thermostat is controlled so as to fall within a predetermined temperature range. Therefore, any IC test apparatus that has been corrected by the unit-specific temperature correction value can be viewed as having the same temperature distribution characteristics in any of the IC test apparatuses. Therefore, in order to calculate the temperature correction value specific to other types of change kit,
Any IC test apparatus may be used as long as it is corrected by the unit-specific temperature correction value.

[0015] This means that the change kit specific temperature correction value measured by the IC test apparatus corrected by the unit specific temperature correction value can be shared by any IC test apparatus. Therefore, by measuring the change kit specific temperature correction value of each type of change kit in advance, the change kit specific temperature correction value
It can also be used for test equipment.

Therefore, if the change kit-specific temperature correction value is measured once for each type of change kit, this correction value may be written to the storage of each IC test apparatus for each change kit. When testing ICs, I
The C test apparatus calculates a correction value obtained by adding a desired change kit-specific temperature correction value to its own device-specific temperature correction value, and uses this correction value as a temperature guarantee correction value.

FIG. 3 shows an example of an operation screen when a change kit is selected in the IC test apparatus. (A) displayed on the screen indicates the unit number assigned to this IC test apparatus. This unit number is distinguished from other units,
A machine-specific temperature correction value unique to this machine is stored according to this machine number. (B) to (M) indicate the type of change kit of each model. By selecting this symbol and inputting it from the input means, the desired change kit specific temperature correction value is read out, and the temperature guarantee correction value is obtained by adding the unit specific temperature correction value and the change kit specific temperature correction value. The temperature of the heater of the constant temperature bath is corrected by the temperature assurance correction value.

In (N) to (T), when a new type of change kit is developed, the specific temperature correction value of the new type of change kit is written in this sign.

[0019]

As described above, according to the present invention, a certain kind of change kit, for example, a ZIP change kit is selected as a reference change kit, and this reference change kit is mounted on an IC tester. A temperature correction method for separately obtaining a unit-specific temperature correction value and a change kit-specific temperature correction value, and combining the unit-specific temperature correction value and the change kit-specific temperature correction value to obtain a temperature guarantee correction value. Therefore, each IC test apparatus only needs to measure the unit-specific temperature correction value.

Further, once the change kit-specific temperature correction value is measured, the correction value can be shared by each IC test apparatus. Therefore, the measurement work relating to the temperature correction of the IC test apparatus can be greatly reduced, and the labor required for shipping can be greatly simplified. Moreover, if the unit-specific temperature correction value is stored for each unit, even if a new type of change kit is developed, only the change kit-specific temperature correction value of that change kit is stored in the storage of each IC test device. The new change kit can be used with guaranteed temperature compensation. Therefore, a new type of change kit can be used even in an IC test apparatus that has already been shipped. Therefore, a highly versatile IC test apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is a graph for explaining a unit-specific temperature correction value used in a temperature correction method according to the present invention.

FIG. 2 is a graph for explaining a change kit specific temperature correction value used in the temperature correction method according to the present invention.

FIG. 3 is a front view showing an example of an operation screen of an IC test apparatus using the temperature correction method according to the present invention.

[Explanation of symbols]

 RF unit specific temperature correction value CH change kit specific correction value

Claims (1)

(57) [Claims] An IC to be tested is provided in accordance with a type of a terminal of the IC to be tested, wherein the IC to be tested is operated in the constant temperature bath to determine whether or not the operation of the IC to be tested is normal. In an IC test apparatus including a change kit configured so that a guide rail for guiding the guide is exchangeably mounted, in a state where the reference change kit is mounted,
The temperature distribution at each test position of the IC under test is measured, and a correction value for correcting the temperature distribution to be within an allowable range is obtained for each temperature within the operating temperature range. With the temperature corrected using this unit-specific temperature correction value as the correction value, the temperature distribution characteristics of other types of change kits are determined, and this temperature distribution characteristic is used as the change kit-specific temperature correction value. A temperature correction method for an IC test apparatus, wherein an actual IC test is performed using a composite value of a correction value and a change kit-specific temperature correction value.