JPS5934173A - Semiconductor testing device - Google Patents

Abstract

PURPOSE:To reduce the increase of an output current by an effective resistance terminal, and to reduce remarkably a rise of a joining temperature of a semiconductor element to be measured, by inserting an element for executing a high speed switching operation, in series with a terminal resistor which is required for measurement of high accuracy. CONSTITUTION:An output of a semiconductor element to be measured 1 is connected to a comparator 7 through a signal line 2, a resistance 3 and a coaxial cable 5. Also, one terminal of the cable 5 is connected to a resistance 8 which is a terminal resistance of the signal line 2 and also takes impedance matching in the terminal of the cable, through a high speed switching element 31 constituted of a J-FET, etc. The switching element 31 is subjected to an opening and closing control by a clock signal TRMCLK. H threshold voltage VOH and L threshold voltage VOL are set to the comparator 7, and a clock signal input terminal 23 for giving the timing for deciding an output signal from the element 1, and an output terminal 24 of the comparator are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor testing device that improves a resistor termination method for impedance matching in a high frequency transmission system.

(2) is one output signal line of the semiconductor device under test (fl), and (3) is a back match resistance for the output signal line (2), that is, for impedance matching with the coaxial cable (5) described later. (4) is a first relay for bussing the first resistor (3); (5) is for transmitting the output signal from the semiconductor device under test (1); coaxial cable, (7) is a comparator that compares and detects the output signal of the coaxial cable (5), +81 is the terminating resistance (load/load resistance) of the upper Je output signal line (2), and the coaxial cable ( (9) is a second resistor for impedance matching at the terminal end of (5), and (9) is a second resistor that mechanically opens and closes according to the output signal from the semiconductor device under test (1).
The relay (GO) is a termination power source for providing the termination potential of the output signal line (2), and aIJ is a drive unit of the test equipment, which is not necessary for the present invention and will not be described in detail. (6) is the terminal of the driving part and detection part of the test equipment, (OH is the comparator (7)
) is the H threshold voltage for determining the H1 output, νQh is the H threshold voltage for determining the LlL output, and (23) is the timing at which the output signal from the semiconductor device under test (1) should be determined. (241 is the output terminal of the Pa5s/Fail signal determined by the comparator (7).

Next, the operation will be explained. Generally, when transmitting a high frequency wave, if the impedance of the transmission line is not matched, reflected waves etc. will be superimposed on the transmitted wave, causing waveform distortion and making accurate measurements impossible. The first resistor (3) is used to eliminate reflected waves generated at the starting end G of the coaxial cable (5), which is the transmission line, and has the same impedance as the coaxial cable (5). Similarly, the second resistor (8) is for eliminating reflected waves at the terminal end (131) of the coaxial cable (5).After eliminating such waveform distortion, the semiconductor device under test ( The output signal from 1) is sent to the comparator (7)
Compare and judge.

In the operational function test of the semiconductor device under test (1), when the time comes for the output signal from the device under test (1) to be determined, the comparator (7) is activated by inputting the clock signal 5nChi at the input terminal. The comparator (7) determines that the output signal VOUT from the device under test (1) is /l (if thicker than Qop, it is H; if it is smaller than Vob, it is ``L+1'', and if it matches the expected value, that is, 10 A P as s/Fa i l signal is outputted to the output terminal t241: Vor if it is less than or equal to H, Pa5s if it is more than H, and l·ail if they do not match.In this way, the A high-speed operation test is performed.The first relay 14) is used to short-circuit the first resistor (3) when it is not needed in case of other test items (for example, DC test). , the second relay (9) is a mechanical relay for opening in case of other test items and when the output signal line (2) is connected to the input terminal of the semiconductor device under test (1). .

Nowadays, semiconductor devices to be measured have become faster and more dense, but the problem of heat generated by the semiconductor devices during operation has become more serious, and semiconductor devices with one step of 2 watts or more have appeared. For this reason, the junction temperature of the semiconductor constituting the semiconductor element is reaching a limit value (usually 100c or less). Heat generation in semiconductor elements is also caused by the operation of internal circuits, but in high-density, multi-bin devices, a large portion is caused by output current. For example, if an output signal with a logic amplitude of 2■ is terminated with 50Ω, 4
A current of QmA flows, and in an element with 100 output pins, a current of 4A flows, which causes heat generation and destroys the semiconductor element (1).

Therefore, in conventional test equipment, a mechanical relay that requires several milliseconds or more for switching is used as the second relay (9).
1) High-speed operation < switching operation of 1Qns or less)
There was a drawback that the semiconductor element fil to be measured was destroyed due to overload. There is also a method of slowing down the operating speed of the semiconductor device under test (1) to the operating speed of one mechanical relay (9), but this method has the disadvantage that it is not possible to test the high-speed operation of the semiconductor device under test (1). be.

The present invention was made to eliminate the drawbacks of the conventional devices as described above, and by inserting a high-speed switching element that performs high-speed switching operation in series with the termination resistor necessary for high-precision measurement, it is possible to achieve effective It is an object of the present invention to provide a semiconductor testing device that can reduce the increase in output current due to resistive termination and drastically reduce the rise in junction temperature of a semiconductor device under test.

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

In Figure 2, (31) is a high-speed switching element composed of a J-FET (junction field effect transistor) or the like with a switching time of 5 nS or less, and (32) is a clock that controls the opening and closing of the high-speed switching element (31). This is the input terminal for the signal ``l''RMCL,K.

FIG. 3 is a timing chart showing the operation of each part of the apparatus of this embodiment, and FIG. 3(a) shows the change over time of the output signal VOI77 from the semiconductor device under test (1), VoL.

Voh is the voltage at each low potential and high potential of about 7L. In addition, the same figure (b) shows a clock signal 5TBCt inputted to the input terminal for activating the comparator (7).
, shows the change over time of x. In addition, (C) in the same figure shows the input terminal (3) that controls the opening and closing of the high-speed switching element (31).
2) shows the change over time of the clock signal -1'+u+CLx input to the high-speed switching element (31).
By closing, the second
This shows the change over time of the output current 10υT that flows into and out of the terminal power supply (]G0 through the resistor (8).

Next, the operation of this embodiment will be explained. The second resistor (8
) is necessary only when the output signal VasT from the semiconductor device under test (1) is determined by the comparator (7) of the test equipment.By the way, the active period T of the comparator (7). is defined by the clock doubler 5TRCLK input to the input terminal (231), and this active period old is
+++ This is only a part of the section where the active layer of the constant semiconductor element (1) is present. Therefore, the fast switching concentrator (31
] is the active NJ l'd of comparator (7)"],"a
It is only necessary to close only the period IHJ Tb including the period before and after. In addition, as shown in Fig. 3, the output current 10UT flowing in and out of the terminal voltage #(10) is connected to the high-speed switching element (3).
1) is ON (closed), I(H'+
Output current 101 (or L output current [OL flows, high-speed switching element (31) is OFF (open)
1" does not flow.

In this way, each part of the test apparatus of this sister example operates according to the timing chart shown in FIG. Period 1 when (31) is ON
11C current flows to the output signal line (2) only in the period 17. By comparing and measuring the output signal from the semiconductor device under test (1) within j Tb with the comparator (7), it is possible to perform high-speed operation tests with high accuracy without significantly increasing the junction temperature of the semiconductor device under test. .

In addition, in the second embodiment, a fed using a J-F'ET was shown as a high-speed switching element, but it is also possible to use an M5FET (8-10S type transistor) or a zero switch. . In addition, instead of the terminal end erosion (earth grounding) or the dosing bar of the test device d may be used.
.

As described above, according to the present invention, by setting one switching element ζj-1W'', 'Ji to 0FF (open), the output current from the semiconductor device to be measured can be made zero, and the output current from the semiconductor device to be measured can be reduced to zero. Since the period of the output signal determined by the comparator can be set to about 1/10 of the operating cycle of the semiconductor device under test, it is possible to reduce the junction temperature of the semiconductor device under test without increasing the junction temperature too much. Moreover, it is possible to perform high-speed operation tests with high accuracy.Furthermore, conventional equipment uses mechanical relays, which have stray capacitance of 10 to 20 pF, so the rise time/fall time of the waveform is There were problems such as the value becoming large, but since this device uses a J = "ET (field effect transistor), the stray capacitance is small at 2 to 5 pF, making it possible to perform high-speed operation tests. .

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing a semiconductor test device using a conventional output signal termination method, FIG. 2 is a circuit diagram showing an embodiment of the present invention, and FIG. 3 is a timing chart showing the operation of the above embodiment. . (1)...Element under test, (3)...First resistor,
(5) Coaxial cable, (7) Output detection circuit, (8) Second resistor, G31) High speed switching element. Agent Makoto Kuzuno - Written amendment (voluntary) 29 Name of the invention Semiconductor testing device 3 Representative Hitoshi Katayama of the person making the amendment Department 4 Agent 5 Detailed description of the invention in the specification subject to amendment Columns and drawings (Figure 3) 6. Contents of the amendment (11 Changed "100°C" on page 4, line 19 of the specification to 1125
℃”. (2) On page 5, line 7, 1, therefore, should be corrected to ``however.'' (3) rV oil, V on page 6, lines 13-14
Correct "oh" to rVol-, VoHJ. (4) Figure 3 is corrected as shown in the attached sheet. ”−

Claims (1)

[Claims] (1) #Conductor A coaxial cable for transmitting the high frequency output signal of the device under test, a first resistor for impedance matching at the starting end of the coaxial cable on the side of the device under test, and a terminal end of the coaxial cable. a second resistor for impedance matching at the end of the coaxial cable; a high-speed switch inserted in series with the second resistor; 1. A semiconductor testing device as set forth in item 1 of the scope of Patent No. 88, characterized in that it is equipped with an output detection circuit for detecting and also serves as a load resistor for a semiconductor test.