JPS6231136A - Device for evaluating photosemiconductor element - Google Patents

Abstract

PURPOSE:To make the evaluation of the optical characteristics of a photosemiconductor element while keeping the element in a wafer state by providing at least one optical fiber in a conventional prove card. CONSTITUTION:An optical fiber 7 is attached to a probe card. One end of the optical fiber 7 is held by an optical fiber holder 8. Another end is connected, e.g., to a photoelectric element or the photoconnector attached to a connector part of a substrate 1. In order to evaluate the optical characteristics of a light accepting part 24 in a photosemiconductor element 23, the beam emitted from a light emitting element 25 composed of semiconductor laser proceeds in the optical fiber 7 and enters in the light accepting part 24 and the electric signals shown in a probe 3 by that beam is observed. Thus, the evaluation of optical characteristics of the photosemiconductor element 23 can be made while keeping the element in a wafer state.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an evaluation apparatus for an optical semiconductor element having a light emitting function or a light receiving function among semiconductor elements.

2. Description of the Related Art A probe card is an apparatus for efficiently measuring and evaluating semiconductor elements formed on a semiconductor substrate called a wafer in a wafer state. As shown in FIG. 4, a probe card normally has a plurality of probes 42 mounted on a substrate 41 made of an insulator so as to be in contact with semiconductor elements.

The distance between each probe 42 is determined so that the tip of each probe 42 comes into contact with a desired pad of the semiconductor device to be measured. The other end of each probe 42 is connected to a copper foil 43 formed on the substrate 41, and is electrically connected to each pin 46 of a connector portion 44 formed on the substrate 41 through the copper foil 43. It is connected.

By bringing the probe 42 into contact with the semiconductor element, the semiconductor element can be evaluated by an externally connected measuring device through the connector section 44. On the other hand, for example, GaAs
In order to evaluate the optical characteristics of a light-emitting element or a light-receiving element formed on a semiconductor substrate such as , InP, etc., each semiconductor element is cut out into chips and assembled, and then each is measured and evaluated separately.

Problems to be Solved by the Invention However, when evaluating semiconductor devices using conventional technology, conventional probe cards are used to investigate the electrical characteristics of optical semiconductor devices formed on a wafer, and good products are separated into individual chips. After cutting out and assembling, the method used was to evaluate the optical characteristics. For this reason, a lot of effort and assembly mounts were required for evaluation. Furthermore, obtaining the distribution of optical characteristics of optical semiconductor elements within the wafer plane from the data obtained in this way requires a huge amount of work, and it is necessary to provide appropriate instructions for the manufacturing process in a short period of time. It was difficult to do.

Means for Solving the Problems The technical means of the present invention for solving the above problems is to evaluate the optical characteristics of an optical semiconductor element by using at least one or more optical fibers in the above conventional probe card. The objective is to enable the process to be carried out in the wafer state.

Effects The effects of this technical means are as follows. In other words, in the same way that multiple probes attached to a probe card are attached at determined intervals so as to contact desired pads of an optical semiconductor element, the probes are attached at fixed intervals so as to make contact with desired pads of an optical semiconductor element. At least one optical fiber is attached to the probe card so as to be optically coupled to the fiber. By aligning the probe card so that it connects to the pad of the optical semiconductor element formed on the wafer, the tip of the attached fiber can be aligned to the light emitting position or the light receiving position, and the tip of the probe card can generate electricity. By applying a predetermined electric signal to the optical semiconductor element using a probe, it is possible to simultaneously evaluate the optical characteristics in the wafer form through the fiber.

Example Embodiments of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a perspective view of one embodiment of the present invention, FIG. 2 is an enlarged sectional view of the probe portion thereof, and FIG. 3 is a sectional view showing another embodiment of the present invention.

In FIG. 1, a plurality of probes 3 are attached to a hole 2 formed in the center of a substrate 1 made of an insulator such as glass epoxy, similar to a conventional probe card. The probes 3 are electrically connected to predetermined pins e of the connector portion 5 of the substrate 1 by copper foils 4 formed on the substrate.

In addition, an optical fiber 7 is attached to the probe card according to this embodiment. One end of the optical fiber 7 is held by an optical fiber support 8. The other end is connected to the photoelectric element 9 or the substrate 1, for example.
It is connected to an optical connector 10 attached to the connector section 6 of.

It can be connected to external evaluation equipment through an optical connector. The photoelectric element 9 is a light-emitting element such as a semiconductor laser when measuring the light-receiving function of an optical semiconductor element as an object to be measured, and a light-emitting element such as a photodiode when measuring the light-emitting function of an optical semiconductor element. Any light receiving element may be used.

The photoelectric element 9 connected to the optical fiber 7 generates an electrical signal, which can be connected to an external evaluation device through the connector section 6.

From now on, when evaluating the light emitting function of optical semiconductor devices,
Since the configuration of the present invention is the same when evaluating the light receiving function, the case where the optical semiconductor element has the light receiving function will be explained.

In FIG. 2, a wafer 22 is placed on a stage 21. Optical semiconductor elements 23 are formed in the same bit in the wafer 22. The ability to evaluate electrical characteristics using the probe 3 is the same as in the conventional probe card. In order to evaluate the optical characteristics of the light receiving section 24 in the optical semiconductor element 23, light emitted from the light emitting element 25 constituted by a semiconductor laser is incident on the light receiving section 24 of the semiconductor element 23 through the optical fiber 7, and its This can be done by observing the electrical signal that appears on the probe 3 due to light. The end of the optical fiber 7 that is brought close to the optical semiconductor element 23 is supported by a support 8 so that the probe 3 can be connected to the optical semiconductor element 2.
When the alignment is performed on the pad of No. 3, the optical semiconductor element 23
The relative position between the probe 3 and the probe 3 is predetermined and fixed so that the probe 3 is aligned with the light receiving section 24 of the probe 3. By moving the stage 21 at every pitch of the optical semiconductor elements 23 on the wafer 22, it is possible to easily evaluate not only the electrical characteristics but also the optical characteristics.

FIG. 3 shows another embodiment of the present invention, in which the light emitted from the light emitting element 26 is guided through the optical fiber 7, and then
The lens 31 and the supporting tube 32 constitute an imaging system, and the focal position is determined by the relative position with respect to other probes 3 so that light can efficiently enter the light receiving section 24 in the optical semiconductor element 23. . Furthermore, optical semiconductor devices are often used for high-speed optical communications and signal processing, and for this purpose, it is necessary to evaluate the optical semiconductor devices by operating them at high speed in a wafer state. Therefore, as shown in FIG. 3, a coaxial cable 33 such as a semi-rigid cable that can pass high-frequency signals is used as a connection line for electrical signals, and a probe 3 as short as possible is attached to the tip of the coaxial cable 33 to connect the optical semiconductor device. Connect with pad 23.

With such a configuration, it becomes possible to evaluate electrical characteristics and optical characteristics during high-speed operation.

Effects of the Invention As described above, according to the present invention, it is possible to efficiently evaluate both the electrical and optical characteristics of optical semiconductor elements in the wafer state, and furthermore, the obtained characteristics can be evaluated on the wafer. It is possible to grasp the distribution state in a short period of time and give appropriate instructions to the manufacturing process.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a probe card according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view of the probe portion of the same probe card, and FIG. 3 is a probe of a probe card according to another embodiment of the present invention. FIG. 4 is a perspective view of a conventional probe card. 1...Substrate, 3...Tip, 7...
...Optical fiber, 9...Photoelectric element, 22...
... Wafer, 23... Optical semiconductor element, 26.
... Light emitting element, 31 ... Lens, 33.
...Coaxial cable.

Claims (4)

[Claims] (1) A probe attached to a substrate made of an insulating material is brought into contact with the semiconductor element to evaluate the semiconductor element, and at least one optical fiber is attached to the substrate at a position near the semiconductor element. Evaluation device for fixed optical semiconductor devices. (2) The optical semiconductor device evaluation device according to claim 1, wherein one end of the optical fiber is connected to a photoelectric device. (3) A patent in which at least one lens is attached to the end of an optical fiber fixed near a semiconductor element, and the lens is arranged so that the lens focuses the surface of the semiconductor element and the end of the optical fiber. Claim 1
An evaluation device for an optical semiconductor device as described in 2. (4) The evaluation device for an optical semiconductor device according to claim 1, wherein the probe has a coaxial cable extending to the vicinity of the surface of the semiconductor device.