JP2539453B2 - Semiconductor element inspection equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a semiconductor element inspection apparatus, and in particular, it is suitable for inspecting the characteristics of a semiconductor element when an object to be inspected has a step or has an obstacle. The present invention relates to a semiconductor device inspection device.

[Conventional technology]

A conventional method for inspecting a semiconductor element is, for example, as shown in FIGS. 5 (a) and 5 (b), vapor deposition, sputtering or sputtering on the edge of the surface of each chip-shaped semiconductor element 2 of a wafer 1 on which a semiconductor element is formed. Electrode 3 formed by plating
As shown in FIG. 6 and FIG. 7, two probes 5 such as tungsten needles projecting obliquely downward from the probe card 4 in opposite directions are used by using the deflection. A method is used in which the tip end is brought into contact with the electrode 3 so as to be scraped, and the electrical characteristics thereof are inspected.

However, in the above-mentioned conventional technique, each probe 5
Since the length is generally several tens of millimeters, the concentrated inductance becomes large and the inspection for high-speed signals is limited.

That is, when the characteristic impedance of the signal line on the probe card 4 is R and the concentrated inductance of the probe 5 is L, the time constant is L / R, and the characteristic impedance of the signal line is now R = 50Ω and the concentrated inductance L = 50
When the time constant is set to nH, the time constant becomes 1 nS, and when a high-speed signal of this level is handled, the rectangular signal waveform is distorted, and accurate inspection cannot be performed. Therefore, it is usually limited to DC characteristic inspection. Further, in the above-mentioned probing system, there is a limit to the spatial arrangement of the probes 5, and it is not possible to cope with the high density of electrodes of the semiconductor element and the increase in the total number.

Therefore, conventionally, for example, as shown in FIG. 8, a chip 2 having a semiconductor element on its electrode (not shown) formed by a solder ball 6 used for solder fusion connection,
As shown in FIG. 9, the method of connecting the electrodes 8 on the surface of the wiring board 7 such as a ceramic multilayer board by solder melting is suitable for high-density mounting and batch connection with high yield, and its application is expanded. ing.

As described above, as the density of semiconductor elements increases, an operation test using high-speed signals is required.
As an inspection method capable of inspecting the characteristics of a semiconductor element having a solder ball for solder melting connection on its electrode in this case, conventionally, for example, it is described in JP-A-58-73129, which is shown in FIG. As shown in FIG. 11, the electrodes of the semiconductor element 2 are formed on the surface of a probe card 11 formed of a multi-layer substrate formed as a line having a constant characteristic impedance with the signal conductor wiring 9 and the power supply conductor layer 10 as reference layers. A protruding electrode 12 formed of nickel or the like plated with nickel is formed at a position corresponding to, and the multilayer substrate 11 is heated from a heat source 13 on the surface opposite to the surface having the protruding electrode 12, 12 is pressed against the solder ball 6 to conduct electricity by melting the solder, exchange signals, and inspect semiconductor devices, and then heat the multilayer substrate 11 again. Protruding electrode 12 by dissolving it
There has been proposed a semiconductor element inspection technique which is carried out by releasing.

[Problems to be solved by the invention]

In the above-mentioned conventional technique, it is a method of inspecting with a probe card composed of a multilayer substrate in which a signal line is formed into a line having a constant characteristic impedance by establishing conduction between a semiconductor element electrode and a protruding electrode by melting solder.

However, with such a method, it is possible to inspect the high-speed electrical characteristics, but since it is necessary to melt the solder balls on the electrodes of the semiconductor element, not only heat stress is applied to the semiconductor element, but also workability is improved. There was a problem that it took a lot of time to perform the inspection. In addition, if there is a cooling fin for self-heating of the semiconductor element or an electrode pad of the substrate on which the semiconductor element is mounted that may be an obstacle during probing such as repair wiring or there is a step on the contacted surface of the probe. Was difficult to inspect by the above method.

In order to inspect the above-mentioned semiconductor element, the semiconductor element is less likely to be stressed in a short time, and it is possible to cope with a high density of a large number of electrodes, electrodes with steps or complicated space arrangement, and high-speed electrical characteristics A measurable inspection device is needed.

An object of the present invention is to provide a device that efficiently and highly reliably implements an operation test using a high-speed signal corresponding to high density of semiconductor devices.

[Means for solving problems]

The above-mentioned objects are a first base material provided with a connecting member electrically connected to an inspection circuit, a first pin serving as an electrical contact with the connecting member, an inspection position of an object to be inspected, and an electrical contact. A probe including a second pin and a conductive tube in which the first pin and the second pin are slidably fitted is fixed to a through hole arranged so as to correspond to the inspection position of the inspection target. The present invention can form the length of the probe to be appropriately short so that the spring and the two movable pins can be inserted.
In particular, the length of the portion of the movable pin protruding outward from the tube can be made short (about 3 mm to 5 mm), so that the disturbance of the high speed signal can be reduced.

Further, since the movable pin is pressed outward by the elastic force of the spring, it can be contacted with a predetermined force even if there is some step on the electrode to be contacted, and the individual probe or By replacing the insulative substrate for the probe retaining plate with the probe, it is possible to easily deal with the repair of the probe or the change of the probing pattern, and by providing the coaxial cable that constitutes the probe with appropriate flexibility. Even if the cooling fin 5 has a complicated space arrangement with an obstacle, the coaxial cable can be curved to deal with the situation.

Therefore, a probing head that targets the electrodes for measuring the electrical characteristics of semiconductor elements that can perform operation tests with high-density, ultra-high pin count and high-speed signals is possible, has good repairability, and can easily change probing patterns. This makes it possible to perform semiconductor element inspections that can be performed and can be inspected efficiently and with high reliability in a short time.

〔Example〕

1 and 2 showing a semiconductor device inspection apparatus according to an embodiment of the present invention will be described below.

In FIG. 1 and FIG. 2, 14 is a supporting base, which is fixed and supported at a fixed position, and the semiconductor element 2 is mounted on the upper surface in the center thereof, and on both sides of the semiconductor element 2 for measuring electric characteristics of the semiconductor element 2. A plurality of electrodes 15 are fixed. Reference numeral 16 denotes a housing, which is supported by a positioning mechanism (not shown) and is formed so as to be movable in two horizontal and vertical directions perpendicular to each other. A conductive substrate 17 and the conductive substrate 17 are provided on the inner opposing surface thereof. Of the probe holding insulating substrate 18 arranged so as to be inserted on both the upper and lower sides of the above, and the core cotton holding insulating substrate 19 that is arranged to face the upper probe holding insulating substrate 18 with a gap, Two sets each of which is fixedly supported by an insulating substrate 19 for holding the cotton wool and a conductive substrate 20 arranged at a vertically opposing position. The probe 21 is provided in the same number as the electrode 15, and the tip end of the tube 21a is always made of a conductive tube 21a formed of brass or the like and the elastic force of the spring 21b loosely fitted in the tube 21a. It is composed of two movable pins 21c and 21d projecting outward from both ends. The conductive substrate 17 has the tube 21a loosely fitted in the through hole 17a having a gap. The probe-holding insulating substrate 18 is made of ceramics or glass or the like, and both ends of the tube 21a are fixedly fitted into the through holes 18a formed at the positions corresponding to the electrodes 15, and the tube 21a. The upper end of each of the movable pins 21c and 21d is bent and fixed right and left on the upper surface of the upper insulating substrate 18 for holding a probe, and the two movable pins 21c and 21d are always opposed to the end faces of the electrode 15 and the electrode 24 for a cotton swab described later. I try to contact them.
The core cotton retaining insulating substrate 19 is formed of ceramics or glass, and the tip of the core cotton 23 is placed in a through hole 19a formed at a position corresponding to the through hole 18a of the probe retaining insulating substrate 18. A flanged electrode 24, which is fixed by solder connection, crimping, laser welding, or the like and is formed of copper or brass, is fixedly supported. The conductive substrate 20 is formed of brass, copper, or the like, and the through hole 20a is formed at a position corresponding to the through hole 19a of the insulating substrate 19 for holding the core cotton.
The core cotton 23 is loosely fitted therein, and the tip end of the shield 22 of the coaxial cable that covers the core cotton 23 is connected by solder 25. The shield 22 of this coaxial cable has its rear end connected to a test circuit (not shown) via a coaxial connector 26.

Since the semiconductor inspection apparatus according to the present invention is configured as described above, the through hole formed in the insulating substrate 18 for holding the probe with an accuracy within a few microns with respect to the electrode 15 for measuring the electrical characteristics of the semiconductor element 2. Probe 2 in 18a
Since it is possible to adopt a method of fixing the tube 21a of 1, it is possible to use the super multi-movable pins 21c, 21d with a density of 3 to 5 times higher than that of the conventional 700 micron pitch, about 200 pieces / cm ² probing device. A probing device that can be positioned can be formed.

Further, since it is loosely fitted in the through hole 17a of the conductive substrate 17 with a gap with the tube 21a of the probe 21, a shielding effect can be obtained by setting the conductivity 17 to the ground potential, and the movable pin 21c, 21d can be provided outside. Since the protruding length can be made short, the concentrated inductance can be made small, and the disturbance of high-speed electrical signals such as crosstalk and reflection can be made as small as possible, and the inductance of all other wiring components can be minimized. Since the matching is achieved, the high-speed electrical characteristics of the semiconductor element 2 can be inspected.

Furthermore, since the fixed portion of the probe 21 and the fixed portion of the shield 22 of the coaxial cable are configured by the movable pins 21c and 21d and the electrode 24, it is possible to easily replace the plurality of probes 21 and thereby the probing pattern. The probe 21 can be easily changed and repaired.
The probes 21 can be easily taken out one by one from the through holes 18a formed in the insulating substrate 18 for holding a probe, so that the individual probes 21 can be easily replaced.

Although the tube 21a is bent to the left and right and fixed to the probe-holding insulating substrate 18 in the above-described embodiment, the present invention is not limited to this. For example, FIG. As shown in (a), the tube 21a
The lower end of the tube is fixed in the through hole 27a of the insulating substrate 27 provided on the lower surface of the lower probe-holding insulating substrate 18, or as shown in FIGS. 3 (b) and 3 (c). When the insulating material 28 having a low dielectric constant such as polytetrafluoroethylene is filled between the through hole 17a of 17 and the length of the probe 21 is short, as shown in FIG. 3 (d). It is conceivable that the probe holding insulating substrate 18 alone or the probe holding insulating substrate 18 and the insulating substrate 27 are used for fixing as shown in FIG. 3 (e).

Regarding the holding of the shield 22 and the core cotton 23 of the coaxial cable, a gap is formed between the dielectric substrate 20 and the core cotton holding insulating substrate 16 as shown in FIG. A dielectric thick film electrode 28 such as silver palladium is embedded in the through hole 19a of the cotton holding insulating substrate 19 and the tip of the core cotton 23 is brought into contact with the conductive thick film electrode 28, and these are connected by solder 29. Alternatively, as shown in FIG. 4 (b), the electrode 30 of copper or brass fixed to the tip of the core cotton 23 by soldering, crimping, or laser melting is made of ceramics or glass. The electrodes 30 are fixed by inserting them into the through holes 31a, 32a of the formed insulating substrates 31 and 32 and shifting the relative positions of these insulating substrates 31 and 32, and the conductive substrate above the electrodes 30 is fixed. 20 to the coaxial cable Field 22
It is also conceivable to connect the tip of the with a solder 25.

〔The invention's effect〕

According to the present invention, a semiconductor element can be efficiently inspected even when an object to be inspected has a step or an obstacle, and position adjustment and repair of each probe at the time of probing are easily performed. Therefore, the probing pattern can be easily changed and the semiconductor element can be inspected by a high-speed electric signal.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing an essential part of a semiconductor device inspection apparatus according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view showing a probing portion shown in FIG. 1, and FIG. ) ~ (E)
Is a cross-sectional view showing another embodiment of the fixed part of the probe shown in FIG. 1, and FIGS. 4 (a) and 4 (b) are other implementations of the fixed part of the shield and core cotton of the coaxial cable shown in FIG. 5 (a) and 5 (b) are perspective views showing the electrode arrangement of a conventional semiconductor element, FIG. 6 is a cross-sectional side view of a conventional inspection probe, and FIG. FIG. 8 is a perspective view showing a semiconductor element having a conventional solder pole on an electrode, FIG. 9 is a perspective view showing a mounting state of a semiconductor element having a conventional solder melting connection, and FIG. The figure which shows the probe card which consists of a multilayer substrate which has a protruding electrode and a heat source,
FIG. 11 is a sectional view of the probe card shown in FIG. 2 …… Semiconductor element, 14 …… Supporting base, 15 …… Electrode, 16 …… Housing, 17 …… Conductive board, 18 …… Insulating board for holding probe, 19 …… Insulating board for holding cotton wool, 20 …… Conductive substrate, 21 …… Probe, 22 …… Coaxial cable shield, 23
...... Core cotton, 24 …… Core cotton electrode, 25, 29 …… Solder, 26 …… Coaxial connector, 27 …… Insulating substrate, 28 …… Insulation material, 30 …… Electrode.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Minor Tanaka Minoru Tanaka, 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa, Hitachi, Ltd. (58) References: 62-123568 (JP, U)

Claims (3)

(57) [Claims] 1. A first substrate having a connecting member electrically connected to an inspection circuit, a first pin serving as an electrical contact with the connecting member, an inspection position of an object to be inspected, and an electrical contact. A probe including a second pin and a conductive tube in which the first pin and the second pin are slidably fitted is fixed to a through hole arranged so as to correspond to the inspection position of the inspection target. And a second substrate described above. 2. The semiconductor element according to claim 1, wherein the connecting member is fixed to a through hole, and the through hole is provided so as to correspond to the position of the through hole provided in the second base material. Inspection device. 3. The semiconductor device inspection apparatus according to claim 1, wherein the connection member and the inspection circuit are electrically connected by a coaxial cable.