Patent Application
20240393386
This application claims the benefit of Taiwan Patent Application Serial 112119415, filed May 24, 2023, the subject matter of which is incorporated herein by reference.
The present invention is related to a probing technology, and, more particularly, to a method for adjusting the position of probing base and probing machine for detecting electrical characteristics of a device under test (DUT) having different pitch of contact pads.
Due to the miniaturization of electronic components, it is necessary to test the function of signal transmission after the semiconductor manufacturing process to ensure the quality of electronic components. In general, when it comes to test the electrical connections between various electronic components in electronic products or to check whether signal transmission is normal or not, the probing machine is typically utilized to analyze the electrical signals and perform signal transmission tests on the DUT.
The conventional inspection equipment for probing test generally includes probe devices and signal testing machines, which are utilized to perform electrical testing on the DUT. In general, for the same DUT, such as a packaged carrier board or a printed circuit board (PCB), for example, there may exist issues that different pitches are formed between the testing contact pads in the same DUT. Therefore, different pitch of contact pads on the DUT requires corresponding probing base for inspection. Therefore, there is a need for developing a detachable probing base having specific pitch of needle tip, and the detachable probing base can be automatically changed according to the pitch of contact pads formed on the DUT.
However, when one probing base is replaced with another probing base having different pitch from the pitch of replaced probing base, in certain scenario of inspection according to different type of probing needles, it is desirable that the probing needle tips can be positioned at optimal range of measurement for probing the DUT. After replacing the probing base, if the position of the probing needle tip cannot be rotatably adjusted to the required location, it may result in the inability to contact the pads on the DUT or lead to poor contact, potentially causing issues such as no electrical signal or signal instability.
Accordingly, there is a need for providing a method for adjusting the position of the probing base and probing machine using the same.
During the electrical testing of packaging substrates or printed circuit boards, there is a further need for specific frequency testing. Therefore, it is necessary to use probing needles with impedance matching such as, one end of a coaxial copper tube is connected to the needle body, or a circuit with impedance matching using a printed circuit board is connected to the needle body, for example for testing DUT. Hence, there is a need for designing probing bases with different pitches of needle tip and impedance matching for different pitches of contact pads formed on the substrate or PCB. Furthermore, the probing needles utilized for testing can adopt a structure with impedance matching and then extend to the needle body conforming to the pitches of the contact pads such as, a coaxial copper tube or a printed circuit board with impedance matching circuits connected to the needle body, for example. Conventionally, the probing needles designed with impedance matching for different pitches of contact pads are integrated with the impedance matching structure through connecting measure such as welding, for example, which causes the pitch between needle bodies incapable of being adjusted. Even if the pitch of needle tip is adjusted, the overall impedance matching of the probing needle will be changed.
In order to solve the above-mentioned issues, the present invention provides a method for adjusting the position of the probing base and probing machine for ensuring stable signal during testing the DUT, and maintaining measurement stability and data accuracy thereby measurement accuracy can be stably kept for different probing needles having various tip pitches.
In one embodiment, the present invention provides a method for adjusting position of probing base, comprising steps of providing a probing machine comprising a probing holder, a first probing base, and a second probing base, wherein the first probing base and the second probing base are positioned in a probing base placing part, the first probing base comprises a first probing needle comprising a plurality of first probing needle bodies, wherein needle tips of two adjacent first probing needle bodies have a first pitch, and the second probing base comprises a second probing needle comprising a plurality of second probing needle bodies, wherein needle tips of two adjacent second probing needle bodies have a second pitch, connecting the probing holder to the first probing base when the first probing base is grabbed, enabling a relative motion between a vision identification module and the probing holder such that the probing holder is moved within the field of view of the vision identification module, capturing a first image of the plurality of the first probing needle bodies through the vision identification module wherein the needle tips of the plurality of first probing needle bodies are captured within the first image; and adjusting position of the first probing base according to the first image so as to adjust the roll angle of the needle tips of the plurality of first probing needle bodies.
Through the aforementioned method, after selecting a probing holder with an appropriate pitch of probing needle, and completing the replacement of selected probing holder, the vision identification module identifies the roll angle status of needle tips of needle bodies according to the first image. Subsequently, the adjustment mechanism is utilized to adjust the roll angle of the needle tips whereby the needle tips of the plurality of needle bodies on the probing holder can be aligned to contact with the contact pads of DUT thereby achieving the effect of automatic adjustment of roll angle of needle tips.
Furthermore, the reason that the vision identification module matches with roll angle of the needle tips adjusted by the adjustment mechanism is for complying with the requirement of probe tip leveling of the needle tips of impedance matching probing needles thereby ensuring compliance with various testing specifications for different types of probing needles and signal stability of DUT during the signal test. For example, in case of a process that probing bases with different pitches of needle tip are connected to the probing holder of the probing machine may lead to probe tip leveling of the needle tips failing to comply with the testing specifications. Therefore, a method for adjusting the position of the probing base is required when the probing base connected to the probing holder is replaced.
With the dimension of the DUT decreases, the dimensions of the contact pads on the DUT are also reduced thereby resulting in a decrease of the pitch between contact pads. In order to test smaller-sized DUT, the dimensions of each needle tip on the probing base are also scaled down. Consequently, the load sensitivity that the needle tips of the probing needles is also increased. If the load is not properly controlled, the variation of the load exerted on the probing needles could easily lead to damage the needle tips or contact pads when the probing needles are moved down to contact the contact pads. To prevent damage to the probing needle or the contact pads, a precise control of the needle pressure and load applied to the DUT is necessary. Therefore, when replacement of probing bases is occurred, additional challenges including precise control of load test and conversion should be overcome.
In one embodiment, the probing machine also comprises a load measuring device. The method for adjusting the position of the probing base further comprises step of adjusting the roll angle of the needle tips of the plurality of first probing needle bodies using an adjustment mechanism. Afterward, the probing holder is moved relatively to the load measuring device whereby the needle tips of the plurality of the first needle bodies contact with the load measuring device thereby generating a load information correspondingly.
Through previously described measure of this embodiment, the load that probing needles exert on the contact pads of DUT can be accurately controlled, thereby preventing the probing needles or contact pads of DUT from being damaged. Furthermore, when probing base is replaced, it is necessary to adjust the roll angle of the needle tips in advance and then perform a precise load control of the probing needle.
In one embodiment, through the aforementioned method of generating load information by the load measuring device, the first probing base comprises a cantilever arm with a pressure sensor formed thereon. The method for adjusting the position of the probing holder further comprises step of generating electrical information by the pressure sensor when the load measuring device generates load information. This load information and the electrical information are then transmitted to a processing unit electrically coupled to the load measuring device and the pressure sensor, wherein the processing unit establishes a correlation between the load information and the electrical information.
Through the previously described measure of the embodiment, when the probing base is replaced, it is necessary to adjust the roll angle of the need tips and then perform a precise control with respect to the load and needle pressure.
In one embodiment, the method for adjusting the position of the probing base further comprises providing a supporting platform on which the probing base placing part and the vision identification module are arranged wherein the supporting platform further comprises an testing area for placing the DUT, and the load measuring device is arranged in the probing base placing part or is arranged between the probing base placing part and the testing area.
Through the method of this embodiment that the load measuring device is arranged in the probing base placing part or between the probing base placing part and the testing area, it indicates that, after the roll angle of the needle tips is adjusted, the load calibration can be promptly conducted so as to save required time of relative movement between the probing holder and the supporting platform, thereby improving utilization.
In one embodiment of the method for adjusting the position of the probing base, the adjustment of the roll angle of the needle tips comprises step of moving the first probing base along a curved surface wherein a plurality of the first needle bodies are located within an inner arc region of the curved surface.
Through the method of this embodiment, when the adjustment mechanism rotates the probing base for adjusting the roll angle of the needle tip through a sliding movement on the inner arc region of the curved guide rail so as to prevent the probing needle from being out of the image-acquiring field, such as FOV, of the image-acquiring module of vision identification module during the adjustment. This is also capable of avoiding the need to spend time locating the probe position during the adjustment, thereby enhancing the efficiency of adjusting the roll angle of the probing needle.
In one embodiment for adjusting the position of the probing base, it further comprises rotating the first probing base by a specific angle after the probing holder is connected to the first probing base such that the first probing base is in the imaging field, such as FOV, of the vision identification module.
Alternatively, through the present embodiment during the process for acquiring image of the needle tip, the probing holder is capable of rotating by a specific angle, particularly the specific angle rotating about the Z axis, so as to prevent the vision identification module form being interfered or to allow the probing needle facing the vision identification module, whereby the vision identification module can acquire the first image of the needle tip.
The present invention provides a probing machine with replaceable probing base, comprising a probing base placing part, a probing holder, a vision identification module, and adjustment mechanism for adjusting probe tip leveling. The probing base placing part is utilized to store a first probing base and a second probing base. The first probing base comprises a first probing needle comprising a plurality of first needle bodies wherein a first pitch is defined between needle tips of any two of adjacent first needle bodies. The second probing base comprises a second probing needle comprising a plurality of second probing bodies, wherein a second pitch is defined between needle tips of any two adjacent second needle bodies. When the probing holder grabs the first probing base, the probing holder is connected to the first probing base utilized to detect electrical characteristics of the DUT. The vision identification module is utilized to acquire a first image with respect to needle tips of the first probing bodies after the probing holder is connected to the first probing base, and generates a control signal according to the first image. The adjustment mechanism receives the control signal for adjusting roll angle of the needle tips of the plurality of first needle bodies of the first probing base.
Through the above-mentioned design, the probing machine can test DUT having different pitches of contact pads by automatically replacing probing base having different pitch of needle tips, such as the probing holder grabs and connects to the first probing base, for example. After replacing the probing base, the vision identification module can identify the probe tip leveling of the needle tips of the needle bodies according to the first image, and adjust probe tip leveling of the needle tips of the needle bodies through the adjustment mechanism such that the needle tips of the needle bodies of the probing base can completely touch the contact pads of the DUT thereby achieving effect of automatically adjusting roll angle of the needle tips. Moreover, the purpose that vision identification module assists the adjustment mechanism to adjust the roll angle of needle tips is to meet the alignment requirement of the needle tip of the impedance-matching probe thereby complying with different testing specification corresponding to different probing needles.
As the size of the DUT decreases, the size of the contact pads on the DUT also decreases, resulting in a reduction in the spacing between the contact pads. In order to test the downsized DUT, the size of each needle tip on the probing base is also reduced. As a result, the sensitivity of the needle tips toward force exerting thereon is increased. If the force applied to the probing needle is not properly controlled, during the process of downwardly probing, it's easy to exceed the critical threshold of the pressure that the probing needle can afford, thereby resulting in damage on the probing needle or the contact pads of the DUT. In order to prevent damage on the probing needle or the DUT, the load that probing needle exerting on the DUT needs to be precisely controlled. Therefore, when replacing the probing base, further efforts are required to overcome issues such as testing load of probing needle, load conversion, and so on.
In one embodiment, the probing machine further comprises a load measuring device, wherein after the adjustment mechanism adjusts the roll angle of needle tips of the plurality of first probing needle bodies, the plurality of first needle bodies are moved to contact the load measuring device thereby generating a load information by the load measuring device.
In one embodiment, the first probing base of the probing machine comprises a cantilever arm having a pressure sensor arranged thereon. When the load information is generated by the load measuring device, and the electrical information is generated by the pressure sensor, both load information and the electrical information are transmitted to a processing unit electrically coupled to the pressure sensor and the load measuring device. Thereafter, the processing unit correlates the load information with the electrical information.
Through the measure provided in this embodiment, it is possible to accurately control the force which the probing needle touches the contact pads of the DUT during downward probing, thereby achieving the effect of preventing damage on the probing needle or the DUT.
In one embodiment, the probing machine further comprises a supporting platform for supporting the probing base placing part and the vision identification module. The supporting platform further comprises a testing area for supporting the DUT, wherein the load measuring device is arranged on the probing base placing part, or is arranged between the probing base placing part and the testing area.
Through the measure of the above-mentioned embodiment, the probing holder is capable of performing probe tip leveling adjustment, and then the load measuring device is utilized to perform load test. When the probe tip leveling of the needle tips is adjusted to the position meet the testing requirement, the load test is then performed so as to achieve the objective that save the relative moving time between the probing holder and the supporting platform, thereby improving the utilization of the probing machine.
In one embodiment, the adjustment mechanism for adjusting the probe tip leveling is arranged on the probing holder, and further comprises a driving unit, a holding part, and a moving part. The holding part is arranged on the probing holder, and comprises a curved guide rail. One side of the moving part is slidably coupled to an arc region of the curved guide rail, while the other side of the moving part is connected to the first probing base. The moving part is also coupled to the driving unit for receiving a power outputted from the driving unit so as to slide on the curved guide rail through the power thereby adjusting the position of the first probing base.
Through the measure of the above-mentioned embodiment, the adjustment mechanism slides on the inner arc region of the curved guide rail; therefore, during the process of adjusting the probe tip leveling of the needle tips, the XY position of the needle tips can be kept near curve center of the curved guide rail, wherein the curve center is relative to the XY position of the image acquiring module of the vision identification module such that the effect that the XY position of the needle tips can be kept within the field of view of the image acquiring module of the vision identification module can be achieved.
In one embodiment, the vision identification module of the probing machine further comprises image acquiring module and identification module, wherein the image acquiring module is utilized to acquire a first image of the needle tips, while the identification module is electrically coupled to the image acquiring module and the adjustment mechanism. The identification module receives the first image and generates a control signal according to the bias angle with respect to the needle tips of the plurality of first needle bodies through identifying the first image.
Through the embodiment of the present invention, the vision identification module can recognize the bias angle of the needle tips of the needle bodies, such that the adjustment mechanism can adjust the roll angle of the first probing base according the identified bias angle described previously.
The present invention will now be specified with reference to its preferred embodiment illustrated in the drawings, in which:
The present disclosure is more particularly described in the following examples that are intended as illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. Like numbers in the drawings indicate like components throughout the views. As used in the description herein and throughout the claims that follow, unless the context clearly dictates otherwise, the meaning of “a,” “an” and “the” includes plural reference, and the meaning of “in” includes “in” and “on.” Titles or subtitles can be used herein for the convenience of a reader, which shall have no influence on the scope of the present disclosure. In addition, the terms used herein generally have their ordinary meanings in the art. In the case of conflict, the present document, including any definitions given herein, will prevail. The same thing can be expressed in more than one way. Alternative language and synonyms can be used for any term(s) discussed herein, and no special significance is to be placed upon whether a term is elaborated or discussed herein. A recital of one or more synonyms does not exclude the use of other synonyms. The use of examples anywhere in this specification including examples of any terms is illustrative only, and in no way limits the scope and meaning of the present disclosure or of any exemplified term. Likewise, the present disclosure is not limited to various embodiments given herein. Numbering terms such as “first,” “second” or “third” can be used to describe various components, signals or the like, which are for distinguishing one component/signal from another one only, and are not intended to, nor should be construed to impose any substantive limitations on the components, signals or the like.
Please refer to
Likewise, the second probing base 20b also comprises a second probing needle 201 having a plurality of second needle bodies 201a˜101c, wherein a second pitch is formed between the needle tips T1 of any two adjacent second needle bodies 201a, 201b, and 201c. The end part of each second needle body 201a˜201c is connected to an impedance-matching structure 201d, such as coaxial copper tube or printed circuit board (PCB) having impedance-matching with the second needle bodies 201a˜201c. In the present embodiment, the impedance-matching structure 201d is coaxial copper tube such that the second probing needle 201 possesses impedance-matching feature. Taking the second probing needle 201 shown in
In the embodiment shown in
Please refer to
After the probing holder 21 grabs the first probing base 20a, the step 12 is performed to enable relative movement between the vision identification module 22 and probing holder 21 such that the probing holder 21 relatively moved to the field of view (FOV) of the vision identification module 22 whereby the vision identification module 22 can acquire first image of the plurality of the first needle bodies wherein the needle tips of the plurality of the first needle bodies are in the first image. In one embodiment, the vision identification module 22 is arranged on the supporting platform 25 such that the probing holder 21 can be moved to the FOV of the vision identification module 22 through relative motion on XY plane. In one alternative embodiment, the supporting platform 25 is controlled to perform two-dimensional motion of XY axes so as to change the relative position between the probing holder 21 and vision identification module 22. In other alternative embodiment, the probing holder 21 and supporting platform 25 can both perform two-dimensional movement such that the relative position between the probing holder 21 and vision identification module 22 can be changed through moving the probing holder 21 and vision identification module 22 simultaneously. In addition to the movement of XY axes, in another embodiment shown in
In one embodiment with respect to the step 12 shown in
After acquiring the first image, the step 13 is performed to adjust the position of the first probing base 20a according to the first image whereby the roll angle of the needle tips T1 of the first needle bodies 200a˜200c can be adjusted. Please refer to the
Next, the way for adjusting probe tip leveling is explained below. The specification of probe tip leveling is varied with the type of the probing needle. For example, in the embodiment shown in
In one embodiment shown in
Next, the operation way of the curved guide rail 233 is explained as
In addition to the adjustment shown in
Please refer to
Please refer back to
The foregoing description of the exemplary embodiments of the disclosure has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to explain the principles of the disclosure and their practical application so as to enable others skilled in the art to utilize the disclosure and various embodiments and with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those skilled in the art to which the present disclosure pertains without departing from its spirit and scope.
| Number | Date | Country | Kind |
|---|---|---|---|
| 112119415 | May 2023 | TW | national |
