Method of testing a packaging sample, method of operating an apparatus for testing of a packaging sample, and apparatus for testing a packaging sample

Abstract

A method of testing a packaging sample with at least one charged particle beam column is described. The method includes placing the packaging sample having a top side facing the at least one charged particle beam column and a bottom side opposite the top side in a vacuum chamber, contacting bottom contact pads provided on the bottom side of the packaging sample mechanically with a plurality of contact pins; directing a charged particle beam of the at least one charged particle beam column on at least a first top contact pad provided on the top side of the packaging sample; detecting signal electrons originating from the top side of the packaging sample; and testing one or more networks on the packaging sample in the vacuum chamber based upon one or more signals comprising the signal electrons.

Description

METHOD OF TESTING A PACKAGING SAMPLE, METHOD OF OPERATING AN APPARATUS FOR TESTING OF A PACKAGING SAMPLE, AND APPARATUS FOR TESTING A PACKAGING SAMPLEFIELD

[0001] The present disclosure relates to a method and an apparatus for testing a packaging sample. More particularly, embodiments described herein relate to the contactless testing of electric interconnections in a packaging sample, for example, including a panel-leveling packing (PLP) substrate, an advanced packaging (AP) substrate, or a wafer level packaging (WLP) substrate by using inter alia charged particle beams, particularly for identifying, characterizing, detecting and / or classifying defects such as shorts, opens, and / or leakages.BACKGROUND

[0002] In many applications, it is necessary to inspect a substrate to monitor the quality of the substrate. Since defects may occur e.g. during the processing of the substrates, e.g. during structuring or coating of the substrates, an inspection of the substrate for reviewing the defects and for monitoring the quality may be beneficial.

[0003] Semiconductor packaging substrates and printed circuit boards for the manufacture of complex microelectronic and / or micro-mechanic components are typically tested during and / or after manufacturing for determining defects, such as shorts or opens, in metal paths and interconnects provided at the substrate. For example, substrates for the manufacture of complex microelectronic devices may include a plurality of interconnect paths for connecting semiconductor chips or other electrical devices, such as logic device circuits, that are to be mounted on the packing substrate.

[0004] The complexity of Advanced Packaging (AP) and Wafer Level Packaging (WLP) substrates is increasing, while design rules (feature size) are decreasingsignificantly. Within such substrates the surface contact points (for later flip chip or other chip mounting) are connected to other surface contact points on the packaging substrate to interconnect semiconductor (or other) devices. Standard methods like electrical-mechanical probing for electrical testing cannot satisfy the requirements of volume production testing, as the throughput decreases (flying prober, higher number of test points) and contacting reliability decreases (electrical prober, smaller contact size). Beyond the reduced size and the problem of potentially damaging contact pads, the topography of the packaging substrates results in difficulties for other test methods, like test methods utilizing capacitive detectors or electric field detectors, because such methods beneficially have a small mechanical spacing.

[0005] A contactless electrical test with an electron beam can be conducted with a voltage signal reading, i.e. voltage contrast by signal electrons detection, such as secondary electrons (SE) and with charging of the test points or networks with an electron beam. The SE energy depends on the starting potential and therefore, the SE signal can be used to measure or evaluate the potential by voltage contrast on different positions on the packing substrate. Electron beam test systems can introduce a DC current in limited regimes to charge networks packaging samples.

[0006] Accordingly, it would be beneficial to provide improved testing methods and testing apparatuses that are suitable for reliably and quickly testing complex microelectronic devices, particularly packaging samples such as samples including Advanced Packaging (AP) substrates, Panel Level Packaging (PLP) substrates, and wafer level packaging samples (WLP).SUMMARY

[0007] In light of the above, a method and apparatuses for testing a packaging sample, a carrier for carrying a packaging sample, and an apparatus for testing of packaging samples are provided according to the independent claims. Further aspects, advantages, and beneficial features are apparent from the dependent claims, the description, and the accompanying drawings.

[0008] According to an embodiment, a method of testing a packaging sample with at least one charged particle beam column is provided. The method includes placing the packaging sample having a top side facing the at least one charged particle beam column and a bottom side opposite the top side in a vacuum chamber; contacting bottom contact pads provided on the bottom side of the packaging sample mechanically with a plurality of contact pins; directing a charged particle beam of the at least one charged particle beam column on at least a first top contact pad provided on the top side of the packaging sample; detecting signal electrons originating from the top side of the packaging sample; and testing one or more networks on the packaging sample in the vacuum chamber based upon one or more signals including the signal electrons.

[0009] According to an embodiment, a carrier for carrying a packaging sample is provided. The carrier includes a carrier body having one or more pockets for receiving one or more packaging samples; and a probe card having a plurality of contact pins configured to contact bottom contact pads of the packaging sample.

[0010] According to an embodiment, an apparatus for testing of a packaging sample is provided. The apparatus includes a vacuum chamber; a stage within the vacuum chamber, the stage being configured to support the packaging sample; a bottom prober with a plurality of contact pins; a charged particle beam column configured to generate a charged particle beam, the charged particle beam column including: a lens assembly with at least a first objective lens configured to focus the charged particle beam on the packaging sample; a first scanner stage configured to scan the charged particle beam to different positions on the packaging sample and a second scanner stage configured to scan the charged particle beam to different positions on the packaging sample; and an electron detector for detecting signal electrons emitted upon impingement of the charged particle beam on the packaging sample.

[0011] Embodiments are also directed at apparatuses for carrying out the disclosed methods and include apparatus parts for performing each described method aspect. Method aspects may be performed by way of hardware components, a computer programmed by appropriate software, by any combination of the two or in any othermanner. Furthermore, embodiments according to the disclosure are also directed at methods for operating the described apparatus and a method for manufacturing the apparatuses and devices as described herein. The methods for operating the described apparatus include method aspects for carrying out functions of the apparatus.BRIEF DESCRIPTION OF THE DRAWINGS

[0012] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments. The accompanying drawings relate to embodiments of the disclosure and are described in the following:

[0013] FIG. 1 shows a schematic sectional view of an apparatus for testing a packaging sample in accordance with any of the testing methods described herein;

[0014] FIG. 2A shows a schematic view of a packaging sample having test points (e.g. contact pads) thereon, wherein a charged particle beam and a bottom prober is used according to embodiments of the present disclosure;

[0015] FIG. 2B shows a schematic view of another example of a packaging the sample at one testing according to embodiments of the present disclosure;

[0016] FIG. 3 shows a schematic view of a carrier for supporting a packaging sample according to embodiments of the present disclosure;

[0017] FIGS. 4A and 4B show schematic views illustrating further embodiments of a carrier for supporting the packaging sample during testing according to embodiments of the present disclosure;

[0018] FIGS. 5A and 5B show schematic views illustrating further embodiments of the carrier for supporting the packaging sample during testing according to embodiments of the present disclosure;

[0019] FIG. 6 shows a schematic view of a portion of a test system according to embodiments of the present disclosure;

[0020] FIGS. 7A and 7B show schematic views illustrating further details for supporting a packaging sample during testing according to embodiments of the present disclosure; and

[0021] FIG. 8 shows a flowchart illustrating methods of operating a charged particle beam column for testing of packaging samples according to embodiments of the present disclosure.DETAILED DESCRIPTION

[0022] Reference will now be made in detail to the various exemplary embodiments, one or more examples of which are illustrated in each figure. Each example is provided by way of explanation and is not meant as a limitation. For example, features illustrated or described as part of one embodiment can be used on or in conjunction with other embodiments to yield yet further embodiments. The intention is that the present disclosure includes such modifications and variations.

[0023] Within the following description of the drawings, the same reference numbers refer to the same components. Only the differences with respect to the individual embodiments are described. The structures shown in the drawings are not necessarily depicted true to scale but rather serve to provide better understanding of the embodiments.

[0024] Embodiments of the present disclosure relate to testing and / or defect review for packaging samples, e.g. packaging substrates such as panel-leveling packing (PLP) substrates, advanced packaging (AP) substrates, or wafer level packaging substrates (WLP). A packaging sample may further include a portion of a packaging substrate, i.e. a unit to be utilized for packaging a device and / or a stack of one or more packaging substrates or units. A packaging sample may further include a fullpackage. The testing and / or defect review is provided according to methods as described herein.

[0025] For contactless testing of a packaging sample, at least one charged particle beam is used for reading charges and optionally writing charges on the packaging sample, particularly for identifying and characterizing defects such as shorts, opens, and / or leakages. A contactless electrical test with a charged particle beam can be provided, wherein a voltage signal reading (e.g. voltage contrast by signal electron sensing) is provided. According to some embodiments, which can be combined with other embodiments described herein, the voltage contrasts on the packaging sample may be determined by detection of signal electrons. According to some embodiments, which can be combined other embodiments described herein, the signal electrons may particularly be secondary electrons. Test points or contact points, for example contact pads, can be charged contactless on a packaging sample, such as at least on a portion of a packaging substrate. Contactless testing avoids or reduces damage to the substrate. Detection and classification of electrical defects is enabled.

[0026] Packaging samples, e.g. AP / PLP / WLP substrates, have a top side, for example, for chip mounting, and a bottom side, for example, for package mounting. The bottom side can include the electrical interface for signals, power, and ground connections. The top side contact pads are typically smaller, with a small pitch, and are sensitive to mechanical damage. Contaminations or scratches on the top side contact pads or top side contacts can cause chip contact failures. Contacting with the charged particle beam, for example, an electron beam, is beneficial. The bottom side contacts are larger with a larger pitch. These contacts can be mechanically contacted (and tested) using probing contacts without causing yield drops. A limitation based upon providing DC current in a limiting regime by a charged particle beam, such as limitations to parametric measurements or of switching logic device circuits, can be overcome by an additional mechanical probing and / or driving.

[0027] Embodiments of the present disclosure, inter alia, relate to an electrical backside driving by a prober for packaging samples to support a charged particle beam test. Using a bottom prober to electrically connect the bottom side ofpackaging samples supports a non-contact charged particle test on the top side. A fast and precise electrical defect detection and characterization for a plurality of different defect scenarios can be provided.

[0028] According to some embodiments, which can be combined with other embodiments described herein, the test, particularly an electrical test of a packaging sample, is provided by a combination of voltage signal reading, for example, sensing the voltage contrast of signal electrons, such as secondary electrons and bottom prober testing. Further, the top contact pads, i.e. the surface contact electrodes at the top side of the packaging sample, and / or the networks (the test points) at the top side of the packaging sample, can be charged with the charged particle beam.

[0029] FIG. 1 shows a schematic view of an apparatus according to embodiments of the present disclosure and illustrates the concept of combined contactless and mechanical-contact testing.

[0030] According to embodiments described herein, a packaging sample 10 is supported on a stage 105. The packaging sample is supported in the vacuum chamber 110. According to some embodiments, which can be combined with other embodiments described herein, the packaging sample 10 can be placed on the stage 105 on a bottom prober 190.

[0031] In the following, reference is, inter alia, made to an electron beam of an electron beam column. A person skilled in the art can understand that the embodiments can be modified by using a charged particle beam of a charged particle beam column, wherein, for example, ions are utilized as primary charged particles and electrons are utilized as signal charged particles.

[0032] As is schematically depicted in FIG. 1 , the electron beam column 120 may be provided on a first side of the stage 105, for example, the top side of the stage 105. The electron beam column 120 has an electron source 121 for generating an electron beam. The beam is accelerated and guided towards the packaging sample 10. As is schematically depicted in FIG. 1 , the electron source 121 is connected to a power supply 130. The power supply can provide a high-voltage to the electronsource for emitting the electron beam, i.e. the primary electron beam, from the electron source. According to some embodiments, which can be combined with other embodiments described herein, the voltage provided by the power supply 130 can be varied to change the energy of the electron beam and, thus, the landing energy of the electron beam on the packaging sample.

[0033] According to some embodiments, which can be combined with other embodiments described herein, a stigmator 126 is provided. The stigmator 126 is configured to reduce astigmatism. Astigmatism can be generated in one or more of the beam optical components of the electron beam column 120. The stigmator is controlled, e.g. by controller 180, to adjust the shape of the electron beam on the packaging sample, particularly at various positions on the packaging samples, i.e. at large and small deflection angles of the electron beam. The shape of the beam is adjusted at positions extending over the field of view (FOV) on the packaging sample.

[0034] A first scan deflector 122 is provided. The first scan deflector 122 can provide a first scanning stage for deflecting the beam over a first area on the packaging sample. A second scanning stage for deflecting the beam over a second area on the packaging sample can be provided according to some embodiments. The second stage can be provided by a second scan deflector 125. According to some embodiments, the deflection fields of the first scan deflector 122 and the second scan deflector 125 may partially overlap or may be adjacent to each other. The second stage can be operated to scan over the second area, which is smaller than the first area.

[0035] Accordingly, a large scanning area and a smaller scanning area, which is added to the larger scanning area, can be provided. By providing a two-stage scanning, a large FOV can be provided while having a precise electron beam positioning, particularly for vector scanning according to some embodiments of the present disclosure.

[0036] According to some embodiments, the first scan deflector 122 can be configured for vector scanning. An improvement of the voltage contrast can beprovided by vector scanning since charges on areas of the packaging sample, which are not to be charged are reduced or avoided. According to some embodiments, a charged particle beam is positioned onto various positions of the packaging sample with a vector scan method, wherein the beam is blanked (deflected away or switched off) between moving from a first position on the packaging sample to a second, subsequent position on the packaging sample.

[0037] According to some embodiments, which can be combined with other embodiments described herein, a plus of a charged particle beam is provided at the desired location, e.g. a first position on a packaging sample and further positions on the packaging sample. According to some embodiments, which can be combined with other embodiments described herein, the vector scanning is provided on a comparably large field of view, for example, the field of view having a size of at least 70 mm or above. Accordingly, improved vector scanning with beam planking and an improved beam positioning can be provided for testing of a packaging sample. According to some embodiments, which can be combined with other embodiments described herein, the field of view can have a size of at least 70 mm or above. Particularly, the field of view is orders of magnitude larger as compared to a scanning electron microscope. According to some embodiments, which can be combined with other embodiments described herein, the field of view (FOV) can be 150 mm or below. Accordingly, the field of view can be smaller than a field of view of a display testing with e.g. 200 mm or 300 mm field of view.

[0038] The vector scan method according to embodiments of the present disclosure, improves the signal-to-noise ratio (S / N-ratio) and the signal difference between good and defect networks, contact pads or contact electrodes. The charged particle beam is turned off or blanked while the deflection system positions on the next to be tested contact pad, i.e. surface contact electrode, on the packaging sample. According to some embodiments, a blanking and un-blanking of the beam with a deflector is beneficial as compared to switching the beam on and switching the beam off. For example, some emitters, like a thermal field emitter or a cold field emitter, have a better performance under stable conditions. The charged particle beam is pulsed on for a defined time and turned off again. The charged particlebeam is only hitting the contact pads or contact electrodes and does not expose the dielectric material in-between. According to some embodiments, which can be combined with other embodiments described herein, the charged particle beam is only hitting conductive areas of the packaging sample. The electron is not hitting dielectric material of the packaging sample. According to some embodiments, which can be combined with other embodiments described herein, vector scanning results in positioning of the electron beam on an arbitrary sequence of positions on the packaging sample.

[0039] For example, the first scan deflector 122 can be a magnetic deflector to cover a larger area of the field of view and the second scan deflector 125 can be an electrostatic deflector to provide the fast deflection within a smaller area. In some embodiments, the apparatus 100 may include a scan controller 123 connected to the first scan deflector 122 of the electron beam column 120 and the second scan deflector 125. The first scan deflector 122 and the second scan deflector 125 may be configured to vector scan the electron beam onto a substrate surface.

[0040] FIG. 1 shows the apparatus 100 having a first plurality of electrodes 146 that can generate a multi-pole field, for example, an octupole field, to guide the signal electrons 113 towards the electron detector 140. For example, the first plurality of electrodes can include eight or more electrodes for generating an octupole field. Particularly, the multi-pole field generated by the first plurality of electrodes 146 can be dynamically adjusted to the position of the electron beam 111 on the packaging sample 10. The second plurality of electrodes 148 can generate a multi-pole field, for example, an octupole field, to guide the signal electrons 113 towards the electron detector 140. For example, the second plurality of electrodes can include eight or more electrodes for generating an octupole field. Particularly, the multi-pole field generated by the second plurality of electrodes 148 can be static. According to some embodiments, which can be combined with other embodiments described herein, one or more electrodes in the electron beam column 120 can be at least one assembly of four or eight electrodes (or more electrodes), configured to generate a multipole field for guiding signal electrons. As shown in FIG. 1 , the one or moreelectrodes 154 having the first plurality of electrodes 146 and the second plurality of electrodes 148 can be integrated in the electron beam column 120.

[0041] According to some embodiments, which can be combined with other embodiments described herein, a beam dump 128 can be provided. The beam dump is configured to block the electron beam, which may be deflected by a further deflector (shown without a reference numeral) towards the beam dump, e.g. into the beam dump 128. The further deflector can be an electrostatic deflector. The electron beam can be deflected into the beam dump for blanking of the electron beam. An aperture can be provided to allow for fast switching of the electron beam, by deflecting the electron beam towards the beam dump. Accordingly, a beam blanker configured to switch the electron beam on or off, particularly to switch the electron beam on or off in the plane of the packaging sample can be provided.

[0042] In the present disclosure, reference is made to “blanking” and “un-blanking” of the electron beam. Blanking of the electron beam is understood as deflecting the electron beam, particularly within the electron beam column, e.g. away from the optical axis. The beam can be deflected, e.g. in a beam dump. Further, blanking of the electron beam can be understood as switching off the electron beam, e.g. by reducing the extraction voltage at the electron source. Un-blanking of the electron beam is understood as deflecting the electron beam onto the optical axis, particularly within the electron beam column. The beam can be deflected, e.g. out of a beam dump. Further, un-blanking of the electron beam can be understood as switching on the electron beam, e.g. by increasing the extraction voltage at the electron source back to normal operation.

[0043] Electron beam testing offers a suitable solution as it allows testing of test points smaller than 60 pm or 10 pm, or even below. It is capable of voltage contrast imaging. The test structures can be charged positive or negative by the electron beam impact, and the test point potential can be determined by the voltage contrast principle for defect detection and sample parameter monitoring (such as capacitance, resistance, etc.).

[0044] Further, the electron beam column, further includes a lens assembly 124 with a first objective lens configured to focus the electron beam on the packaging sample and, optionally, a second objective lens to focus the electron beam on the packaging sample. FIG. 1 shows a smaller, second objective lens being provided at a similar position than the first objective lens. The objective lenses may be electrostatic, magnetic, or a magnetic-electrostatic. The first objective lens can have a stronger focusing strength than the second objective lens, e.g. the first objective lens can be configured to have a stronger focusing strength than the second objective lens. Accordingly, coarse focusing can be provided by the first objective lens, and fine focusing can be provided by the second objective lens. Yet further, according to some embodiments, which can be combined with other embodiments described herein, the second objective lens can be faster than the first objective lens, i.e. a change of the focusing strength can be changed faster. According to some embodiments, which can be combined with other embodiments described herein, the second objective lens is configured for a smaller hysteresis as compared to the second objective lens. By providing two objective lenses, a large FOV can be provided while having a precise focus control of the electron beam.

[0045] The apparatus 100 further includes an electron detector 140 for detecting signal electrons 113, e.g. secondary electrons, emitted upon impingement of the electron beam on the packaging sample, and an analysis unit 141 configured to determine, based on the signal electrons 113, if e.g. a device-to-device electrical interconnect path 20 of the packaging sample is defective. For example, test point potential can be determined by the voltage contrast principle for defect detection. The voltage contrast can, for example, be provided by detecting signal electrons with an electron detector 140, e.g. including an Everhard-Thornley detector. An energy filter 142 for the signal electrons 113 may be arranged, e.g. at the electron detector 140, particularly in the path of the signal electrons towards the Everhard- Thornley detector, as schematically depicted in FIG. 1 . The energy filter may include a grid electrode configured to be set on a predetermined potential. The energy filter 142 may allow the suppression of low-energy signal electrons. The energy filter 142 may suppress signal electrons that are irrelevant for the voltage contrast measurements to be conducted. In some implementations, the energy filter 142 maysuppress signal electrons emitted from uncharged surface areas and may only let through signal electrons emitted from a charged surface contact point or contact pad. Accordingly, the signal current detected by the electron detector may depend on the energy of the signal electrons, indicating whether a probed surface contact point is defective or not.

[0046] According to an embodiment, the apparatus for testing of a packaging sample includes a vacuum chamber and a stage within the vacuum chamber, the stage being configured to support the packaging sample. The apparatus includes a bottom prober with a plurality of contact pins and a charged particle beam column configured to generate a charged particle beam. The charged particle beam column includes a lens assembly with at least a first objective lens configured to focus the charged particle beam on the packaging sample, a first scanner stage configured to scan the charged particle beam to different positions on the packaging sample, and a second scanner stage configured to scan the charged particle beam to different positions on the packaging sample. For example the first scanner stage can be a magnetic scanner stage and the second scanner stage can be an electrostatic scanner stage. The charged particle beam column further includes an electron detector for detecting signal electrons emitted upon impingement of the charged particle beam on the packaging sample and, optionally, a beam blanker configured to blank or un-blank the charged particle beam. The test apparatus may further include a controller having a processor and a memory, storing instructions that, when executed by the processor, cause the apparatus to perform a method according to any of the embodiments described herein.

[0047] The testing method described herein is suitable for testing packaging samples for multi-device in-package integration, e.g. for testing PLP substrates, AP substrates, WLP substrates, or combinations thereof, including combinations of one or more of such substrates and devices or dies. An electron beam can be used for both, charging e.g. the device-to-device electrical interconnect path and for reading the charged circuitry voltage, particularly by probing one or more surface contact points with the electron beam. Yet further voltages and / or currents can be provided via the bottom prober. With respect to the electron beam, both the “electrical driving”and the “probing” can be done with an electron beam, and particularly in combination with a bottom prober having contact pins such that defects can be reliably and quickly found. Testing by electron beam charging and electron beam probing from top is independent of topography, fast, and flexible with regard to contact point positions, size and geometry, whereas the topography of the packaging sample may be a problem for other test methods like capacitive or electric field detectors.

[0048] The combination of electromechanical probing of the bottom side and the electron beam test on the top side, merges various advantages from both methods. An electron beam testing offers a suitable solution to allow non-contact testing of test points, e.g. contact pads, sized 60 pm or below or even 10 pm or below. Electron beam testing, e.g. with voltage contrast imaging, positively or negatively charged test structures can be tested (electron beam reading), wherein a test point potential can be determined by the voltage contrast principle. Further, test structures can be charged positively or negatively with the electron beam (electron beam writing). The electrical test by a prober on the bottom side contact pads of a packaging sample enables electrical driving of the works and / or parametric measurements, particularly while the non-contact electron beam test on the top side ensures fast and damage-free testing for electrical defects.

[0049] According to an embodiment, a method of testing a packaging sample with at least one charged particle beam column is provided. The method includes placing the packaging sample having a top side facing the at least one charged particle beam column and a bottom side opposite the top side in a vacuum chamber. The method further includes contacting bottom contact pads provided on the bottom side of the packaging sample mechanically with a plurality of contact pins and directing a charged particle beam of the at least one charged particle beam column on at least a first top contact pad, provided on the top side of the packaging sample. Signal electrons originating from the top side of the packaging sample are detected, and testing one or more networks on the packaging sample in the vacuum chamber based upon one or more signals including the signal electrons can be provided.

[0050] Fig. 2A shows a packaging sample 10, for example, a packaging substrate. The packaging sample 10 is supported on a bottom prober 190. The bottom probed can include a carrier having a carrier body 202 and the plurality of contact pins 204. The contact pins contact bottom contact pads on the bottom side of the packaging sample. The packaging sample further includes, for example, the first top contact pad 21 and a second top contact pad 22. The electron beam 111 is scanned onto the positions of the packaging substrates to impinge on the top contact pads. Signals can be provided to the bottom contact pads via the plurality of contact pins. Particularly, different voltages and / or voltage variations over time can be provided to the bottom contact pads and, more particularly to the bottom contact pads individually. According to some embodiments, which can be combined with other embodiments described herein, a method of testing a packaging sample further includes providing signals to the bottom contact pads. For example, the signals can include drive signals driving logic device circuits in the packaging sample. For example, the plurality of transistors can be switched on or off individually to switch circuits in the packaging sample, or the like.

[0051] Further, according to some embodiments, which can be combined with other embodiments described herein, the signals provided to the bottom contact pads can include signals for parametric measurements. The plurality of contact pins, for example, contact pins of a prober (mechanical prober) provide electrical voltages and / or currents to the bottom contact pads. The resulting response of networks in the packaging sample is measured, wherein parameters are extracted. For example, the parameters can be resistance, capacitance, voltage, current or transistor characteristics, such as threshold voltages or leakage current. Specifications of networks and particularly logic device circuits within the network can be tested.

[0052] According to some embodiments, which can be combined with other embodiments described herein, signals provided to the contact pins 204 can influence one or more potentials (voltages) of the top contact pads. Accordingly, individual predetermined voltages can be applied to one or more of the top contact pads in the event the packaging sample is not defective. In the event a defect ispresent in the packaging substrate, one or more of the top contact pads may not be biased to the predetermined voltages. The electron beam 111 can be utilized to read the potentials of the top contact pads.

[0053] Electron beam testing can measure signals of signal electrons when the primary electron beam impinges on a measurement position, e.g. on a contact pad. A difference between a low signal height 211 and the proper signal height 213, e.g. the signal indicative of a defective connection and a signal indicative of a good connection, is shown in FIG. 2A. With a method of testing including vector scanning and beam blanking, at a first position, for example at the position of contact pad numbered as 1 , the electron beam is blanked (deflected away or switched off) after measuring the contact pad numbered as 1. The electron beam 111 is vector scanned to a second position. For example, the second position can be any of the positions of contact pads numbered as 2, 3, or 4. The electron beam 111 is unblanked (deflected on-axis or switched on). For example, the electron beam can be unblanked (deflected on-axis or switched on) for a period of time. A pulse of an electron beam can be provided on the second position. The electron beam is only directed to contact pads, i.e. tests electrodes of, for example networks. Based upon such proper beam control, charging of dielectric material is reduced or avoided. Accordingly, the difference between a low signal height 211 and the proper signal height 213, can be provided, and particularly, well above a signal-to-noise ratio.

[0054] FIG. 2B shows another schematic view of a packaging sample 10. FIG. 2B shows a cross-sectional view of various components stacked together as a packaging sample. The packaging substrate 11 is provided. For example, the packaging substrate 11 can be a panel level packaging substrate, an advanced packaging substrate, a wafer level packaging substrate, an interposer, or another substrate. A second packaging substrate 12 is stacked on the packaging substrate 11 . For example, the second packaging substrate 12 can be a panel level packaging substrate, and advanced packaging substrate, a wafer level packaging substrate, an interposer, or another substrate. A semiconductor die 13, e.g. forming or including a device or a device module is contacted to the second packaging substrate 12. For example, an organic device can be provided on, or in, a packagingsubstrate and / or, in a packaging sample. The packaging sample according to embodiments of the present disclosure can be one or more packaging substrates. For example, the one or more packaging substrates can be connected to each other and / or, stacked on top of each other. Further, one or more of the packaging substrates of the packaging sample may have a semiconductor die, a semiconductor device, and / or a semiconductor device module coupled to the one or more packaging substrates.

[0055] A packing sample, such as a PLP substrate, may include a plurality of device- to-device connections, e.g. 5.000 or more, 10.000 or more, 20.000 or more, or even 50.000 or more. The connections may include Through Silicon Vias (TSVs), e.g. provided in a silicon interposer with other conductor lines extending through the packaging sample, and / or, may include multi-die interconnect bridges that may be embedded in the packaging sample. The packaging sample may be a multi-layer substrate including electrical interconnections in a plurality of layers arranged on top of each other, e.g. in a layer stack.

[0056] The packaging sample 10 shown in FIG. 2B has bottom contact pads. For example, the first bottom contact pad 221 and a second bottom contact pad 222 are shown. The bottom contact pads are contacted with contact pins of, for example, a bottom prober. The packaging sample 10 further includes, for example, the first top contact pad 21 and a second top contact pad 22. One or more electron beams can be directed on the top contact pads for writing and or reading on the top contact pad. Particularly, one electron beam 111 is subsequently directed to the top contact pads, particularly by vector scanning.

[0057] The combination of the test methods can be beneficial. As shown in FIG. 2B, the top side contact pads, such as the first top contact pad 21 and a second top contact pad 22, are smaller (such as 60 pm or below, or even 20 pm or below), particularly with a smaller pitch (such as 60 pm or below). The top contact pads are sensitive to mechanical damage. Contaminations and / or scratches on the top contact pads can cause chip contact failures and, thus, a failure of the final device. The bottom contact pads, such as the first bottom contact pad 221 and a second bottom contact pad 222, are larger (such as 100 pm or above), particularly with alarger pitch (such as 200 pm and above). These contacts can be mechanically contacted, e.g. for tests using mechanical probing. Thus, a variety of tests can be provided including, contacting the bottom contact pads without causing yield drops.

[0058] According to some embodiments, which can be combined with other embodiments described herein, the bottom contact pads have at least one of a size of at least 80 pm or above and a pitch of 160 pm or above, and wherein the top contact pads have at least one of a size of 40 pm or below and a pitch of 80 pm or below.

[0059] As compared to testing with an electron beam from the top side of the packaging substrate, wherein the packaging substrate may be on a floating potential or may be grounded, contacting bottom contact pads with contact pins allows for individual signal generation at one or more bottom contact pads. Accordingly, a variety of tests of the packaging sample 10 can be provided.

[0060] FIG. 8 shows a flowchart illustrating methods of testing a packaging sample according to embodiments of the present disclosure. At operation 802, the packaging sample is placed in the vacuum chamber. For example, the packaging sample can be supported on a stage. The packaging sample can be directly supported on the stage or via carrier as explained in more detail below. The packaging sample has a top side or generally, a side facing a charged particle beam column, and a bottom side, wherein the bottom side is opposite the top side. Bottom contact pads at the bottom side of the packaging sample are contacted with a plurality of contact pins at operation 804. For example, the bottom contact pads are mechanically contacted with a prober, including the contact pins. A charged particle beam, for example, an electron beam, is directed on a top contact pad on the top side of the packaging sample at operation 806. Upon impingement of the electron beam on the top contact pad, the signal electrons are released. At operation 808, signal electrons originating from the top side of the packaging sample are detected. One or more networks are tested at operation 810 on the packaging sample based upon signals, wherein the signals include at least the signal electrons.

[0061] According to some embodiments, which can be combined with other embodiments described herein, the testing of one or more networks can include testing bottom -to-bottom networks, connecting bottom contact pads by contacting the bottom contact pads mechanically, testing top-to-top networks connecting top contact pads with the electron beam, testing top-to-bottom networks connecting bottom contact and top contact pads by contacting the bottom contact pads mechanically and with the electron beam, and combinations thereof. Additionally or alternatively, the testing of one or more networks can include driving voltages and / or currents into driven bottom contact pads and reading voltages on top contact pads connected to the driven bottom contact pads, measuring electrical parameters of bottom -to-bottom networks connected to bottom contact pads, provide driving patterns of voltage and / or current for parametric testing of the top-to-bottom and bottom -to-bottom networks, and testing top-to-top networks with the electron beam, and combinations thereof.

[0062] In a packaging sample or packaging substrate, top surface networks (top-to- top networks and / or top contact pads can be tested by an electron beam (e.g. with a voltage contrast method). The substrate bottom side is electrically contacted by a bottom prober. The bottom prober can drive voltages / currents into bottom contact pads of the substrate, particularly while the electron beam only needs to read the connected top contact pads. Since some test sequences will have no charging with the electron beam, only reading with the electron beam is faster. The bottom prober can measure electrical parameters (open, short, resistance, capacitance, leakage, etc.) of the bottom-to-bottom networks. The bottom prober allows for dedicated driving patterns of voltages / current configured for parametric testing of the top-to- bottom networks and the bottom-to-bottom networks.

[0063] Particularly, the operation of the at least one electron beam column can include the directing of an electron beam of the at least one electron beam column with a first landing energy on at least a first portion of the packaging sample, and the directing of the electron beam of the at least one electron beam column with a second landing energy different from the first landing energy on the packaging sample. For example, the at least first portion is the first contact pad, and whereinthe signal electrons are detected from the first contact pad and / or a second contact pad.

[0064] According to some embodiments, which can be combined with other embodiments described herein, a charge control during writing of a charge can be provided by operating the electron beam column with a defined landing energy. Particularly, the landing energy, i.e. the energy of the electron beam upon impingement of the packaging sample, can be varied to control the charge provided on the packaging sample. By variation of the landing energy, an area of impingement of the electron beam can be charged positively, negatively, or not charged. During a writing operation, no charge is beneficially provided to the packaging sample. A contactless electrical test can be provided with an electron beam, wherein the charge can be at, for example, a first surface contact point, and charge can be read at, for example, a second surface contact point. This enables the detection and classification of electrical defects of the packaging sample. The different electron beam landing energies (Upe) control the SE yield (secondary electron yield) and, thus, the total electron yield.

[0065] In light of the comparably large amount of dielectric material on a packaging sample, it is beneficial if the electron beam is directed on conducting portions, for example, contact pads only. Accordingly, vector scanning, wherein the electron beam jumps from one position to the other position while being blanked during the movement of the electron beam, is beneficial. At operation 812, a method may include the optional step of vector scanning the electron beam from one test position to another test position.

[0066] Thus, for some embodiments of the present disclosure it is beneficial if the charged particle beam is precisely blanked (or turned on / off). The charged particle beam is beneficially positioned accurately to hit only the contact pad, i.e. surface contact electrode. The charged particle beam is aligned on the packaging sample, and based upon the position calibration. According to some embodiments, which can be combined with other embodiments described herein, the position calibration procedure compensates for several charged particle beam position deviations and particularly, for all charged particle beam position deviations, for example, includingtest substrate position errors and distortions. Further, the focus and / or shape of the charged particle beam is well-defined and, particularly under all deflection conditions, i.e. large or small charged particle beam deflection angles. According to some embodiments, substrate warping may additionally be compensated by providing a distortion alignment specific to a sample, i.e. measuring alignment marks on a sample with a predetermined warping. The position calibration can by modified with a sample specific distortion transformation.

[0067] According to some embodiments, which can be combined with other embodiments described herein, a signal pattern can be provided to the bottom contact pads as illustrated by operation 814. Accordingly, test patterns can be provided which provides improved testing with an electron beam at top contact pads. According to some embodiments, the bottom contact pads can be mechanically connected with a bottom prober directly or via carrier.

[0068] FIG. 3 shows a packaging sample 10 disposed on a carrier 390. A plurality of contact pins 204 are provided. The plurality of contact pins 204 are configured to contact bottom contact pads of the packaging sample 10. The packaging sample includes top contact pads, for example, first top contact pad 21 and second top contact pad 22. According to some embodiments, the top contact pads are smaller, at least by a factor of 2, as compared to the bottom contact pads. The carrier 390 can include one or more clamps 310. For example, the clamps can secure the packaging sample 10 on the carrier. For driving one or more signals, particularly individually to the bottom contact pads, the contact pins can be connected with line 302 carrier pads 304. For example, the carrier pads can be configured to be contacted from the top. The needle probe card may be provided in a test apparatus to contact the carrier pads 304.

[0069] According to some embodiments, a needle prober provided in a test apparatus to contact carrier pads can have a standardized design. By providing different carrier designs for different packaging samples, different arrangements of bottom contact pads, and optionally different designs of the lines 302, can be used to adapt specific packaging sample designs to a standardized needle prober in the test apparatus. Accordingly, a test apparatus can be utilized flexibly to test differentpackaging samples, including when providing a mechanical contact from the bottom. An adaptation of the test apparatus to different packaging samples can be provided by the design of a carrier, and particularly by the pattern of the plurality of contact pins 204 and the electrical connections provided by lines 302. The carrier pads 304 may have a standard geometry and / or standard pattern.

[0070] FIGS. 4A and 4B show two packaging samples 10 disposed in a carrier 490. For example, the carrier 490 includes two substrate receiving pockets in a carrier body 492, each with an opening at a bottom side and the top side. Accordingly, top contact pads, for example, the first top contact pad 21 and a second top contact pad 22 can be exposed at a top side of the carrier 490. Further, bottom contact pads, for example, the first bottom contact pad 221 and a second bottom contact pad 222 are exposed at the bottom side of the carrier 490. A plurality of contact pins 204 can be provided at a probe card 405 of the carrier. Further, the stage 105 can include the support for supporting the carrier 490.

[0071] The contact pins 204 may be provided on the probe card or another plate that may be lifted up and down as indicated by the arrows in FIGS. 4A and 4B. The packaging samples 10 can be secured in the carrier 490 by clamps 310. Upon movement of the stage 105 and the probe card 405 relative to each other, the contact pins 204 can be connected to the packaging samples 10 as illustrated in FIG.4B. Further, as illustrated in FIG. 4A, the stage 105 and the support or probe card 405 can be moved relative to each other to disconnect the bottom contact pads of the packaging samples 10. As shown in FIGS. 4A and 4B, the probe card 405 or corresponding plate can be moved up and down. Alternatively, the stage 105 can be moved up and down to connect and disconnect the bottom contact pads from the contact pins. Accordingly, the networks to be tested can be via the contact pins or can be provided on a floating potential. Particularly, contact pads and / or networks can be biased individually with the contact to the contact pins.

[0072] FIGS. 5A and 5B illustrate further embodiments of a carrier 590. For example, the carrier 590 can be configured to support one or more packaging samples 10. FIGS. 5A and 5B illustrate an example with a carrier 590 supporting two packaging samples in a carrier body 592. The carrier 590 includes a plurality of contact pins204. The carrier body 592 can include openings 593 being configured to receive lift pins 507. The lift pins 507 can be coupled to a plate 505 of the carrier 590. Further, a support for the carrier 590, e.g. a portion of the stage 105 is provided. Upon movement of the plate 505 and the stage 105 relative to each other, the lift pins 507 can lift the packaging samples 10 in the carrier 590. The packaging samples 10 can be secured in the carrier body 592 by clamps 310. Upon movement of the stage 105 and the plate 505 relative to each other, the contact pins 204 can be connected to the packaging samples 10 as illustrated in FIG.5B. Further, as illustrated in FIG. 5A, the stage 105 and the plate 505 can be moved relative to each other to disconnect the bottom contact pads of the packaging samples 10. Accordingly, the networks to be tested can be via the contact pins or can be provided on a floating potential. Particularly, contact pads and / or networks can be biased individually with the contact to the contact pins.

[0073] According to some embodiments, which can be combined with other embodiments described herein, a packaging sample can be moved, e.g. raised and lowered, within a carrier 590, particularly to connect and disconnect the bottom contact pads from the contact pins provided in the carrier. As shown in more detail in FIGS. 7A and 7B, the clamp 310 can include a spring 710 or another flexible element to allow for movement of the packaging sample within the carrier 590 upon actuation of the lift pins 507.

[0074] According to some embodiments, which can be combined with other embodiments described herein, the carrier 590 may further include one or more carrier pads 304. The carrier body 592 may serve as or may include a probe card having the contact pins. The carrier pads can be utilized for providing one or more voltages of the plurality of contact pins 204. For example, individual voltages can be provided to the contact pads. As another example, one or more contact pins 204 can be grounded. Accordingly, a carrier 590 (similar to the carrier 390) can be contacted with one or more probe needles from the top side. As compared to FIGS. 4A and 4B, a carrier 590 as shown in FIGS. 5A and 5B can be more easily exchanged in a test apparatus 100 to provide for different patterns of contact pins, for example, for testing different packaging samples 10.

[0075] FIG. 6 shows a portion of a test apparatus to illustrate embodiments of combining an electron beam test with an electron beam 111 and mechanical contact with contact pins 204. One or more packaging samples 10 are provided in a carrier 490. The probe card 405 has an opening 692 to allow for alignment of the packaging sample with a camera 610. For example, the camera can be a CCD camera. The camera can image of a portion of the packaging sample, for example, a portion having an alignment mark. The image of the portion of the packaging sample is utilized to align the packaging sample 10 and the probe card 405 with respect to each other. For example, the packaging sample and probe card can be aligned in X-direction and in Y-direction as illustrated in FIG. 1. Accordingly, the contact pins 204 and the bottom contact pads can be aligned such that a contact can be provided for each contact pin when the sample is in contact with the plurality of contact pins.

[0076] According to some embodiments, which can be combined with other embodiments described herein, the bottom prober may include a micro-electrical mechanical system (MEMS). In a MEMS, both electronic and moving parts are incorporated and particularly, the mechanical parts, e.g. contact pins can be precisely positioned based upon electrical signals. The contact pins can be provided with a MEMS to align the contact pins of a probe card of the bottom prober to the plurality of bottom contact pads.

[0077] For a carrier 590 as shown in FIGS. 5A and 5B, an opening configured to provide a visual alignment path can further be provided in the carrier 590, to allow an optical alignment through the plate and the carrier.

[0078] The contact pins 204 are connected via a switching matrix 622 to a tester 624. The tester can be an open-short tester providing currents and / or voltages to the contact pins. The switching matrix can be utilized to switch the currents and / or voltages of the tester 624 to different contact pins. Different networks can be tested by the voltages and / or currents of the tester 624 by switching the voltages and / or currents to different contact pins, e.g. contact pins of the stage or the carrier. The electron beam 111 can be directed to top contact pads of the packaging sample to allow for combined testing with contact pins and the electron beam.

[0079] FIGS. 7A and 7B illustrate further details of a carrier 590. The carrier may include one or more protection pads 712 at the one or more openings 593. For example, a protection pad may be provided at the position of an opening 593. Thus, upon actuation of a lift pin, the protection pad is urged against the packaging sample. Rather, a protection pad contacts the packaging sample as a lift pin. Thus, a sensitive surface of the packaging sample is less likely damaged. According to some embodiments, which can be combined with other embodiments described herein, the one or more opening and one or more protection pads may be provided at an edge region of the packaging sample or another region, in which the density of bottom contact pads is sufficiently low to allow for positioning of a protection pad. Particularly, one or more protection pads (and / o corresponding openings 593) can be provided in an edge region of the packaging sample. The lift pin is configured to move the protection pad, which in turn moves the packaging sample for lifting or lowering the packing sample in the carrier body 592. One or more springs can provide a force action against a force of the lift pins. The packaging sample can be secured in the pocket of the carrier body 592.

[0080] According to an embodiment, A carrier for carrying a packaging sample is provided. The carrier includes a carrier body having one or more pockets for receiving one or more packaging samples and a probe card having a plurality of contact pins, configured to contact bottom contact pads of the packaging sample.

[0081] Particularly, a pocket of the one or more pockets or each of the one or more pockets can have a minimum dimension of 5mm or above. In light of the comparably large size of packaging substrates, the positioning resolution relative to the size of the substrate is reduced, i.e. a good positioning accuracy is provided relative to the site of the substrate.

[0082] According to some embodiments, the probe card can be movable with respect to the carrier body. The probe card and carrier body can be moved relative to each other, particularly for connecting and disconnecting the probe pins from the packaging sample. According to some embodiments, the carrier body includes the probe card and the carrier further includes openings in the carrier body configured to receive lift pins and a plate being movable with respect to the carrier body andincluding the lift pins. The carrier body can serve as the probe card or can include the probe card. Different carrier designs can be provided for different packaging samples. By providing different carrier designs for different packaging samples, different arrangements of contact pins, and optionally different designs of the lines 302, can be used to adapt specific packaging sample designs to a standardized needle probe card in a test apparatus. Accordingly, a test apparatus can be utilized flexibly to test different packaging samples also when providing a mechanical contact from the bottom. For example, a plurality of carrier pads larger than the contact pins and electrically connected to the contact pins can be provided. The carrier pads can be provided in a standard configuration for the test apparatus. Further, the carrier pads can be provided in a region outside pockets of the carrier body and may have a size that make a mechanical probing less complex.

[0083] As described with respect to FIG. 1 , an apparatus for testing a packaging sample is provided. According to an embodiment, the apparatus for testing of a packaging sample includes a vacuum chamber and a stage within the vacuum chamber, the stage being configured to support the packaging sample. The apparatus includes a bottom prober with a plurality of contact pins and a charged particle beam column configured to generate a charged particle beam. For example, the bottom prober can include a carrier according to any of the embodiments of the present disclosure. The charged particle beam column includes a lens assembly with at least a first objective lens configured to focus the charged particle beam on the packaging sample, a first scanner stage configured to scan the charged particle beam to different positions on the packaging sample and a second scanner stage configured to scan the charged particle beam to different positions on the packaging sample. For example, the first scanner stage can be a magnetic scanner stage and the second scanner stage can be an electrostatic scanner stage. The charged particle beam column further includes an electron detector for detecting signal electrons emitted upon impingement of the charged particle beam on the packaging sample, and beam blanker configured to blank or un-blank the charged particle beam. The test apparatus may further include a controller having a processor and a memory, storing instructions that, when executed by the processor, cause theapparatus to perform a method according to any of the embodiments described herein.

[0084] FIG. 1 shows a controller 180. According to some embodiments, which can be combined with other embodiments described herein, the controller can be connected to one or more of the components of the apparatus 100 for contactless testing of a packaging sample and for contacting the packaging sample from a bottom side thereof. As exemplarily shown in FIG. 1 , the controller can be connected to the power supply 130, the scan controller 123, the analysis unit 141 , and the stage 105. The controller may also be connected to the electron detector 140. According to some embodiments, which can be combined with other embodiments described herein, the controller may further be connected to one or more of a prober card, a switching matrix, a tester (e.g. tester 624 shown in FIG. 6), and an actuator to move the contact pins relative to the packaging sample as explained with respect to any of FIGS. 4A to 5B and 7A to 7B.

[0085] The controller 180 includes a central processing unit (CPU), a memory and, for example, support circuits. To facilitate control of the apparatus for testing packaging samples, the CPU may be one of any form of general purpose computer processor that can be used in an industrial setting for controlling various chambers and sub-processors. The memory is coupled to the CPU. The memory, or a computer readable medium, may be one or more readily available memory devices such as random access memory, read only memory, hard disk, or any other form of digital storage either local or remote. The support circuits may be coupled to the CPU for supporting the processor in a conventional manner. These circuits include cache, power supplies, clock circuits, input / output circuitry and related subsystems, and the like. Inspecting process instructions are generally stored in the memory as a software routine typically known as a recipe. The software routine may also be stored and / or executed by a second CPU (not shown) that is remotely located from the hardware being controlled by the CPU. The software routine, when executed by CPU, transforms the general purpose computer into a specific purpose computer (controller) that controls the apparatus operation, such as that for mechanical contacting and testing, contactless writing and reading with a charged particle beam,and / or vector scanning. Although the method and / or process of the present disclosure is discussed as being implemented as a software routine, some of the method steps that are disclosed therein may be performed in hardware as well as by the software controller. As such, embodiments of the invention may be implemented in software as executed upon a computer system, and hardware as an application specific integrated circuit or other type of hardware implementation, or a combination of software and hardware.

[0086] The controller may execute or perform a method of testing a packaging sample with a charged particle beam, e.g. an electron beam column, according to embodiments of the present disclosure. According to an embodiment, an apparatus for testing of packaging samples with any of the methods described herein is provided. The apparatus may include the controller 180. The controller includes a processor and a memory, storing instructions that, when executed by the processor, cause the apparatus to perform a method according to embodiments of the present disclosure.

[0087] The complexity of packaging samples has been increasing for years, with the aim of reducing the space requirements of semiconductor packages. For reducing the manufacturing costs, packaging techniques were proposed, such as 2.5D ICs, 3D-ICs, and wafer-level packaging (WLP), e.g. fan-out WLP. In WLP techniques, the integrated circuit is packaged before dicing. A “packaging sample” as used herein relates to a packaging sample configured for an advanced packaging technique, particularly a WLP-technique or a panel-level-packing (PLP)-technique. The packaging sample according to embodiments of the present disclosure can be one or more packaging substrate. For example the one or more packaging substrates can be connected to each other and / or stacked on top of each other. Further, one or more of the packaging substrates of the packaging sample may have a semiconductor die, a semiconductor device, and / or a semiconductor device module coupled to the one or more packaging substrates. The packaging sample may also be a complete package that has been assembled.

[0088] “2.5D integrated circuits” (2.5D ICs) and “3D integrated circuits” (3D ICs) combine multiple dies in a single integrated package. Here, two or more dies areplaced on a packaging substrate, e.g. on a silicon interposer or a panel-level- packaging substrate. In 2.5D ICs, the dies are placed on the packaging substrate side-by-side, whereas in 3D ICs at least some of the dies are placed on top of each other. The assembly can be packaged as a single component, which reduces costs and size as compared to a conventional 2D circuit board assembly.

[0089] A packaging sample typically includes a plurality of device-to-device electrical interconnect paths for providing electrical connections between the chips or dies that are to be placed on the packaging sample. The device-to-device electrical interconnect paths may extend through a body of the packaging sample in a complex connection network, vertically (perpendicular to the surface of the packaging sample) and / or horizontally (parallel to the surface of the packaging sample) with end points (referred to herein as surface contact points) exposed at the surface of the packing substrate. The networks in a packaging sample can include bottom -to-bottom networks connecting bottom contact pads, top-to-top networks connecting top contact pads, top-to-bottom networks connecting bottom contact and top contact pads. A packaging sample may also include, e.g. within a packaging substrate, electronic components, such as resistors, capacitors, inductances, or other electrical components, and a logic device. For example, a plurality of transistors can be provided in a packaging substrate.

[0090] An advanced packaging (AP) substrate provides the device-to-device electrical interconnect paths on, or within, a wafer, such as a silicon wafer. For example, an AP substrate may include Through Silicon Vias (TSVs), e.g. provided in a silicon interposer, other conductor lines extending through the AP substrate. A panel-level-packaging substrate is provided from a compound material including, for example, ceramics and glass materials.

[0091] PLP substrates are manufactured that are configured for the integration of a plurality of devices (e.g., chips / dies that may be heterogeneous, e.g. may have different sizes and configurations) in a single integrated package. Further, AP substrates may be combined on a PLP substrate. A panel-level substrate typically provides sites for a plurality of chips, dies, or AP substrates to be placed on a surface thereof, e.g. on one side thereof or on both sides thereof, as well as a plurality ofdevice-to-device electrical interconnect paths extending through a body of the PLP substrate.

[0092] According to embodiments of the present disclosure a packaging sample including one or more packaging substrates (and optionally further components) can be tested with an electron beam from one side, such as the top side. The electron beam can write charges on top contact pads and can read charges of top contact pads, particularly for testing of networks. Further, a bottom prober, e.g a mechanical bottom prober, with contact pins contacting bottom contact pads of the packaging sample is provided. Test sequences of contactless testing and bottom contact testing can be combined.

[0093] Further, the packaging samples according to embodiments of the present disclosure may include different materials, for example, semiconductor material, ceramics, or glass as compared to printed circuit boards. Additionally or alternatively, active or passive electronic components, for example, capacitors, coils, transformers or transistors may be included or embedded in the packaging sample or a die coupled to a packaging substrate of a packaging sample. In addition, a variety of further active and passive components could be embedded in the substrates, which also require electrical tests. Thus, different charging effects can be given, such that a combined testing according to embodiments of the present disclosure is beneficial.

[0094] Yet further, the line width of electrical interconnect paths can be 20 pm or below, e.g. in a range of 20 pm down to 2pm, or even below. Additionally or alternatively, the size of contact pads can be of 60 pm or below or even about 10 pm or below. Accordingly, as compared to a printed circuit board, the failure rate characteristics of an AP / PLP / WLP substrate is more critical, and testing that is inclusive of an electron beam is beneficial.

[0095] Notably, the size of a panel-level-substrate is not limited to the size of a wafer. For example, a panel-level-substrate may be rectangular or have another shape. Specifically, a panel-level-substrate may provide a surface area larger than the surface area of a typical wafer, e.g., 1000 cm2or more. For example, the panel-levelsubstrate may have a size of 30 cm x 30 cm or larger, 60 cm x 30 cm or larger, 60 cm x 60 cm or larger.

[0096] A “surface contact point” or “contact pad” may be understood as an end point of an electrical interconnect path that is exposed at a surface of the packaging sample, such that, particularly at the top side of the packaging sample, an electron beam can be directed on the surface contact point for contactless charging or probing the electrical interconnect path. A surface contact point is configured to electrically contact a chip, a die, a smaller package, or other electrical components like capacitors, resistors, coils, or the like, that is to be placed on the surface of the packaging sample, e.g. via soldering.

[0097] In some embodiments, the analysis unit 141 may be configured to determine, based on the detected signal electrons, whether an electrical interconnect path of a packaging sample has a defect, such as a short, an open and / or a leakage. Optionally, the analysis unit 141 may be configured to classify a detected defect. In some embodiments, the analysis unit 141 may be configured to determine, based on the detected signal electrons and / or via the contact pins from subsequent measurements, whether a short or a leakage exists between two or more electrical interconnect paths. In some implementations, the signal electrons 113 detected by the electron detector 140 may provide information about an electric potential of the substrate location from which the signal electrons 113 are emitted or reflected, and the analysis unit 141 may be configured to determine from said information if the device-to-device electrical interconnect path 20 is defective or not. The analysis unit 141 may be further configured to classify a determined defect.

[0098] Charged particle beam testing, e.g. electron beam testing allows non-contact testing of test points, particularly top contact pads, smaller than 60 pm or 10 pm, and even below. In combination with a backside contact, particularly a full backside contact, advantages of both methods can be combined. A contactless voltage reading (or writing) can be provided on the top side electrodes or top contact pads and a direct electrical measurement and driving can be provided at the bottom side electrodes or bottom contact pads. For example, the top-to-bottom networks can be driven from the bottom and read from the top.

[0099] While the foregoing is directed to some embodiments, other and further embodiments may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

CLAIMSWhat is claimed is:1 . A method of testing a packaging sample with at least one charged particle beam column, the method comprising: placing the packaging sample having a top side facing the at least one charged particle beam column and a bottom side opposite the top side in a vacuum chamber; contacting bottom contact pads provided on the bottom side of the packaging sample mechanically with a plurality of contact pins; directing a charged particle beam of the at least one charged particle beam column on at least a first top contact pad provided on the top side of the packaging sample; detecting signal electrons originating from the top side of the packaging sample; and testing one or more networks on the packaging sample in the vacuum chamber based upon one or more signals comprising the signal electrons.

2. The method of claim 1 , further comprising: providing signals to the bottom contact pads.

3. The method of claim 2, wherein the packaging sample includes one or more logic device circuits.

4. The method of claim 3, wherein the signals comprise driving signals driving the one or more logic device circuits.

5. The method of any of claims 2 to 4, wherein the signals comprise signals for parametric measurements.

6. The method of any of claims 2 to 5, wherein the signals change a voltage of the at least first top contact pad to influence the signal electrons.

7. The method of any of claims 1 to 6, wherein the testing of one or more networks comprises: testing bottom -to-bottom networks connecting the bottom contact pads by the contacting the bottom contact pads mechanically; testing top-to-top networks connecting top contact pads with the charged particle beam; and testing top-to-bottom networks connecting bottom contact and top contact pads, by contacting the bottom contact pads mechanically and with the charged particle beam.

8. The method of any of claims 1 to 7, wherein the testing of one or more networks comprises: driving voltages and / or currents into the bottom contact pads and reading voltages on top contact pads connected to the driven bottom contact pads; measuring electrical parameters of bottom -to-bottom networks connected to bottom contact pads;provide driving patterns of voltages and / or currents for parametric testing of top-to-bottom and bottom-to-bottom networks; and testing top-to-top networks with the charged particle beam.

9. The method of any of claims 1 to 8, wherein the bottom contact pads have at least one of a size of 80 pm or above and a pitch of 160 pm or above, and wherein the top contact pads have at least one of a size of 40 pm or below and a pitch of 80 pm or below.

10. The method of any of claims 1 to 9, wherein operation of the at least one charged particle beam column comprises: directing a charged particle beam of the at least one charged particle beam column with a first landing energy on at least a first portion of the packaging sample; and directing the charged particle beam of the at least one charged particle beam column with a second landing energy different from the first landing energy on the packaging sample.11 . The method of claim 10, wherein the first portion is the first top contact pad, and wherein the signal electrons are detected from the first top contact pad and / or a second top contact pad.

12. The method of any of claims 1 to 11 , further comprising: blanking the charged particle beam of the at least one charged particle beam column at the first top contact pad;vector scanning the charged particle beam from the first top contact pad on the packaging sample to a second top contact pad on the packaging sample while the charged particle beam is blanked; un-blanking the charged particle beam onto the second top contact pad; blanking the charged particle beam at the second top contact pad; and vector scanning the charged particle beam from the second top contact pad to a third top contact pad on the packaging sample while the charged particle beam is blanked.

13. The method of any of claims 1 to 12, wherein the bottom contact pads are mechanically connected with a bottom prober directly or via carrier.

14. A carrier for carrying a packaging sample, comprising: a carrier body having one or more pockets for receiving one or more packaging samples; and a probe card having a plurality of contact pins configured to contact bottom contact pads of the packaging sample.

15. The carrier of claim 14; wherein the probe card and the carrier body are movable relative to each other.

16. The carrier of claim 14, wherein the carrier body includes the probe card and the carrier further comprises: openings in the carrier body configured to receive lift pins; anda plate being movable with respect to the carrier body and including the lift pins.

17. The carrier of any of claims 14 to 16, further comprising: a plurality of carrier pads larger than the contact pins and electrically connected to the contact pins.

18. An apparatus for testing of a packaging sample, comprising: a vacuum chamber; a stage within the vacuum chamber, the stage being configured to support the packaging sample; a bottom prober with a plurality of contact pins; a charged particle beam column configured to generate a charged particle beam, the charged particle beam column comprising: a lens assembly with at least a first objective lens configured to focus the charged particle beam on the packaging sample; a first scanner stage configured to scan the charged particle beam to different positions on the packaging sample and a second scanner stage configured to scan the charged particle beam to different positions on the packaging sample; and an electron detector for detecting signal electrons emitted upon impingement of the charged particle beam on the packaging sample.

19. The apparatus of claim 18, further comprising: a controller having a processor and a memory, storing instructions that, when executed by the processor, cause the apparatus to perform a method according to any of claims 1 to 13.

20. The apparatus of any of claims 18 to 19, wherein the first scanner stage is a magnetic scanner stage and the second scanner stage is an electrostatic scanner stage.

21. The apparatus of any of claims 18 to 20, wherein the bottom prober comprises a carrier according to any of claims 14 to 17.

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