Test arrangement, automated test equipment, and method for testing a device under test including a circuit and an antenna coupled to the circuit

Abstract

One embodiment according to the present invention is a test arrangement for testing a DUT comprising an active circuit and an antenna coupled to the circuit. The test arrangement comprises a DUT position and a probe. In addition, the test arrangement comprises a ground region which is configured to serve as an antenna ground region for the antenna of the DUT. The probe can be positioned near the ground region. The ground region comprises minute openings such that the antenna feed impedance is not affected or is not significantly affected. The DUT position is on a first side of the ground region, while the probe is arranged on a second side of the ground region. The probe is adapted to be weakly coupled to the antenna of the DUT via the opening in order to detect a signal when the circuit of the DUT feeds the antenna of the DUT, and / or in order to couple a signal fed by the antenna to the circuit of the DUT to the antenna.

Description

Technical Field

[0001] Embodiments of the present invention relate to a test arrangement for testing a device under test including a circuit and an antenna coupled to the circuit. Other embodiments according to the present invention relate to an automated test equipment having single or multiple sites for testing a device under test including a circuit and an antenna coupled to the circuit. Other embodiments according to the present invention relate to a method for testing a device under test including a circuit and an antenna coupled to the circuit. Embodiments according to the present invention relate to a system and method for over-the-air electronic testing of an integrated circuit having an embedded antenna array or a module incorporating an integrated circuit. Background Art

[0002] With the continuous push for integration, miniaturization, and wireless connectivity, a new generation of devices for wireless applications (such as 5G or WiGig) is being developed, which includes communication antennas in the integrated circuit wafer or package instead of being separate as in previous generations. These antennas are typically implemented as array antennas with multiple elements.

[0003] Wireless mobile or nomadic communication at millimeter-wave frequencies ensures gigabit-per-second data rates per user. Therefore, both WLAN-based and / or cellular 5G standards envision user access at frequencies such as up to 28 GHz, 39 GHz, 60 GHz, or higher. To achieve the relevant link distances, despite the high free-space attenuation at millimeter-wave frequencies, for example, high-directivity antennas can be employed at both ends of the link, on the base-station side as well as on the user-device side. To support mobility and / or flexibility, for example, electronic beam steering using, for example, the phased-array principle can be employed on the user-device side.

[0004] The millimeter-wave spectrum provides frequency bandwidth resources for, for example, high-throughput or high-data-rate wireless transmission. Therefore, for example, 5G wireless communication as well as advanced WiFi systems envision the use of millimeter waves. According to Friis transmission equation

[0005]

[0006] where

[0007] ·P rec and P t are the received power and the transmitted power,

[0008] ·G rec and G t are the antenna gains,

[0009] ·r is the distance,

[0010] ·and λ0 represents the wavelength of the signal in air,

[0011] High free space loss or high attenuation per unit distance at millimeter wave frequencies can be compensated for by high gain antennas, for example, at one or both ends of a wireless link. High gain antennas have a narrow beam width. For mobile or nomadic applications, for example, the beam direction of the antenna can be appropriately adjusted and pointed towards the opposite end of the link. This includes adjusting the polarization.

[0012] For compactness, low cost, and low loss between transceiver electronics and the air interface, packaged integrated antenna array modules are favored, which include one or several multi-transceiver integrated circuits together with a multi-layer planar antenna array. The form factor of the antenna array plays an important role, so a two-dimensional planar array with a beam preferably having dual linear polarization perpendicular to the array can be used together with a beam originating from a linear array with end-fire, preferably lateral radiation.

[0013] For example, most applications rely on electronic beam steering and / or beam switching and do not rely on mechanical means to change the beam direction, but are achieved by using an antenna array. Although not strictly required, many antenna arrays still place the radiating elements of the array close to each other, for example, to avoid radiation in unwanted directions or constructive interference of the corresponding contributions of the radiators of the array. For a planar array, the typical distance or center-to-center distance between the elements of the array is, for example, about 0.6 times the wavelength λ0 (which is the free space wavelength).

[0014] Thus, a general antenna array consists of a plurality of radiator elements on a plane, each radiator element allowing radiation in two orthogonal, isolated polarizations in a direction perpendicular to the plane and in a spatial sector centered on that perpendicular axis. The array can be periodic in two directions in the plane, with a period of 0.6×λ0.

[0015] The standard operation of such an antenna array, for example, involves predictable constructive interference of all radiation contributions from the array elements in a given spatial direction. This requires a well-defined (preferably for both polarizations including transmit and / or receive electronics) operation of each radiator element in terms of amplitude and phase.

[0016] Rather complex integrated circuits can combine, for example, up to 32 transceiver channels and / or built-in self-test functions on a chip. The complete radiation module incorporates one or several integrated transceiver chips as well as a multi-layer board with signal distribution and an antenna array, exhibiting significant packaging complexity and thus requiring testing during production.

[0017] In addition, for example, a user device can include several radiation modules at different, spatially separated locations of the device, and it can operate in a multi-beam or MIMO mode. This particularly involves testing the full capabilities of such user devices in over-the-air (OTA) tests.

[0018] In the past, antennas were not included in the device under test (DUT), and these devices were tested through electrical connections using standard radio frequency (RF) measurement techniques. A wireless DUT with an integrated antenna array in a wafer or package can be tested in its mission mode through a reciprocal antenna or antenna array that measures wireless signals from the DUT and / or can also provide an excitation signal to the DUT. In other words, a DUT with an integrated antenna array can be tested not only in the transmit mode of the DUT but also, or in some cases required to be, in the receive mode of the DUT. An automated test equipment (ATE) or system for testing these types of devices requires a method and probes and / or antennas to wirelessly receive and excite the DUT, also known as over-the-air (OTA) testing.

[0019] A standard measure for measuring a DUT using an integrated antenna array is to use a standard off-the-shelf antenna, such as a horn antenna, in a far-field measurement region on a properly shielded measurement enclosure (which indicates far from the DUT).

[0020] The operation of the array can be tested by measuring the surrounding space at a certain well-defined distance using a probe in order to plot the radiation intensity in all spatial directions for transmit measurement (while receive measurement is similar). This concept is typically implemented in an anechoic chamber for antenna measurements with spherical scanning capabilities. In addition to the mechanical complexity of precise spherical scanning, the distance between the array and the probe antenna can be quite large, and the measurement may be carried out in the far-field region of the array antenna. The minimum distance of the far field is approximately 2×D

[0021] / λ0, where D represents the maximum size of the antenna array, typically the diagonal length of the array aperture. In mid- to high-gain millimeter-wave arrays, this far-field distance can be several meters. 2 Adjusting traditional anechoic chamber measures for far-field measurement becomes a very expensive investment due to the large number of antenna probes connected to test transceivers that need to be installed in the anechoic chamber. This measure is also not practical for production testing due to the long measurement time for each device.

[0022]

[0023] ​While such a measure is well-suited for laboratory-type measurement setups, it may not be integrable into standard test cells for high-volume testing of integrated circuits due to the required dimensions. Additionally, by operating in the far-field region with a single antenna, it measures the DUT antenna array as a single beam, indicating that all antenna elements are radiating and their signals are combined into a single beam rather than each element on the DUT antenna array separately. If the probing antenna is brought close to each individual antenna element of the antenna array on the DUT, the measuring or probing antenna itself will interfere with the DUT antenna array elements and invalidate the measurement.

[0024] Alternatively, the probe can preferably perform a spherical scan around the antenna array at a short distance in the so-called radiative near-field. These measurement data including amplitude and / or phase can be mathematically transformed to the far-field by using Fourier transform. To some extent, these data can also be transformed towards the antenna array until the local field distribution across the radiation aperture is obtained or approximated. Then, individual faulty antenna array radiator elements can be located.

[0025] Returning to traditional near-field measurements, i.e., electrically characterizing them by probing in the radiative near-field of a large radiative structure and then performing a mathematical transformation, is not helpful because the measurement time of the DUT becomes large as, for example, all spatial directions need to be scanned.

[0026] For production testing or for calibration of a complete radiation module, it may be sufficient to characterize the path of the air interface from a given transceiver of the radiation module to the connected radiator elements. Assuming a test mode of the radiation module supports sequential testing of all transceivers, a single probe antenna placed in front of the array antenna (at a small distance from it or in the radiative near-field of the antenna array but still in the far-field of a single radiation element of the array) can be used for such testing.

[0027] In other words, the operation of probing a single antenna array radiator in amplitude and phase along with the associated transmit or receive chain in a single spatial direction. If this works as required, it is assumed that the radiation properties in all other directions (including coupling with other array elements) also work. The latter assumption is based on design, simulation, or prior measurements of known good devices. An example of such a measure is when the probe antenna is placed in front of the array. The elements of the array are selected one by one. The distance between the antenna array and the probe antenna is such that the probe antenna is in the radiative near-field of the array antenna but in the far-field of a single radiation array element. A non-reflective and / or absorptive enclosure allows for a compact setup.

[0028] Although the concept is simple, there are several drawbacks. First, as a sequential concept, it may take more time than more parallelized measures. Second, depending on the geometry of the setup, the probe antenna "sees" the individual radiating elements of a large antenna array in a compact setup at different angles, so absolute measurements are rather complex and thus only comparisons with a known good device seem simple. Third, the coupling from the "on" radiator elements to other radiator elements may be superimposed on the measured response in a rather complex way (such as via free space but not in the far field and / or via surface waves on the board and / or via transceiver mismatch) and may not be reliably quantifiable.

[0029] In view of this situation, there is a need for a concept that improves the trade-off between complexity, accuracy, and cost in testing a DUT that includes a circuit and an antenna coupled to the circuit. Summary of the Invention

[0030] According to one aspect of the present invention, it has been found that it is advantageous to test a DUT wirelessly in a very close range to the DUT within a so-called near-field electromagnetic operating range. This not only avoids integration and / or mechanical problems of solutions that work in a far-field electromagnetic operating range (where the measurement antenna needs to be far from the DUT), but also allows measurement of each individual antenna element on the DUT antenna array.

[0031] According to one embodiment of the present invention is a test arrangement for testing a DUT, for example using an ATE, the DUT including an active circuit (such as an MMIC) and an antenna coupled to the circuit.

[0032] The test arrangement includes a DUT position and a probe. In addition, the test arrangement includes a ground plane area (such as a metal plane) having a typical size of about λ0×λ0, which is configured to serve as an antenna ground plane area for the antenna of the DUT. The probe can be positioned near the ground plane area, for example within a small distance of λ0 / 20 or less.

[0033] The ground plane area includes a small opening having a size, for example, less than or equal to 0.2×λ0, such that the antenna feed impedance is not affected or not significantly affected. The DUT position is on a first side of the ground plane area, while the probe is arranged on a second side of the ground plane area.

[0034] The probe is adapted to weakly couple to the antenna of the DUT via the opening in order to detect signals when the antenna of the DUT is fed by the circuit of the DUT, and / or in order to couple signals fed from the antenna to the circuit of the DUT to the antenna.

[0035] The test arrangement can be easily integrated on current automated test units used to electronically test a large number of integrated circuits.

[0036] In other words, the novel detection concept or test arrangement can be used to test (preferably planar) antennas in a chip embedded package, such as an embedded wafer level ball grid array (eWLB) package, where the ground plane required for the antenna is part of the circuit board on which the module is to be mounted and is provided, for example, by a ground area having the opening (where the probe is arranged behind the opening when looking from the antenna).

[0037] The proposed concept or test arrangement can be applied to test antennas within a package that require an external reflector, such as a reflector on the board. Such a DUT is, for example, an eWLB package having a dipole and / or patch antenna, where the circuit board on which the package is to be mounted provides a metallic ground for the antenna radiator.

[0038] To test such a package including an antenna, the tester provides a ground at a defined location. This ground will subsequently become part of the antenna. The test lines on the back side can be used to detect the current induced in the ground metal through a small opening in the ground. Detecting the current can include weak detection, i.e., detecting with a significant attenuation between the antenna and the probe to avoid disturbing the antenna operation.

[0039] In a preferred embodiment, the probe is conductive. The conductive probe can guide the wave excited by the antenna to the feed point, or can guide the wave from the feed point to the DUT by exciting the antenna of the DUT.

[0040] In a preferred embodiment, the probe forms a transmission line or is part of a transmission line such as a microstrip line formed by the probe and a ground area (e.g., on the side avoiding the DUT). The probe can optionally be short - circuited to the ground area, for example, within a small distance of λ0 / 20 or less from the small opening in the ground area for coupling. For example, a transmission line is a structured design for conducting radio - frequency alternating current and taking into account their wave characteristics. Thus, waves can be guided via the transmission line, allowing the evaluation of the signal radiated by the antenna.

[0041] In a preferred embodiment, the probe allows weak coupling to the antenna and allows the measurement of the antenna signal that is significantly different from other surrounding signals.

[0042] In a preferred embodiment, the ground area and / or the probe are integrated into the DUT position of the DUT test device. Integrating the ground area and the probe into the DUT position enables a compact test arrangement with a small size.

[0043] In a preferred embodiment, the probe is arranged to couple to the field leaking through the opening in the ground plane region to detect the signal radiated by the antenna of the DUT (primarily) in the direction on the first side of the ground plane region. Coupling to the field through the small opening in the ground plane region allows detection of the signal radiated by the DUT from the second side of the ground plane region to the direction of the first side of the ground plane region, so it allows keeping the size of the test arrangement small.

[0044] In a preferred embodiment, the micro opening and the probe are positioned in the central region of the ground plane region which serves as the ground plane region for the patch antenna of the DUT. In some cases, positioning the probe and the opening in the central region of the ground plane region can maximize the signal received from the antenna of the DUT and / or keep the influence of the opening and the probe on the DUT quite small.

[0045] In a preferred embodiment, the DUT position includes at least one contact region in which contact means for contacting the DUT are arranged, such as spring pins or spring-loaded contacts. The ground plane region behind which the probe is arranged is located beside the contact region such that when the DUT is placed in the DUT position, the contacts of the DUT contact the contact means, and such that when the DUT is placed in the DUT position, the integrated antenna of the DUT is near the ground plane region. The DUT position including the contact region allows, for example, powering the active circuit or antenna of the DUT. In addition, it can allow data transfer between the circuit of the DUT and the test arrangement.

[0046] In a preferred embodiment, the ground plane region behind which the probe is arranged is arranged between two contact regions of the test arrangement. The contact regions are associated with the same DUT such that when the DUT is placed in the DUT position, the integrated antenna of the DUT arranged between the two contact regions of the DUT is near the ground plane region behind which the probe is arranged.

[0047] In some cases, to maximize space utilization, this preferred embodiment can include more than one (e.g., two) contact regions. Different types of DUTs may require different contact means and / or contact regions.

[0048] In a preferred embodiment, the ground plane region behind which the probe is arranged is in the plane having the contacts for contacting the DUT, such that when the DUT is coupled to the contacts, the distance between the ground plane and the DUT is the same as the distance to the surface of the printed circuit board on which the DUT will be mounted, within a distance of + / - 20%.

[0049] Thus, when the DUT is correctly inserted into the test arrangement and connected via the contacts of the test arrangement, the ground plane region replaces the ground plane and the printed circuit board.

[0050] Thus, the test arrangement can be used to probe the signals of the antenna of a DUT in a near-realistic scenario, where the antenna of the DUT is near a circuit board that includes connectors or contact pads and a ground plane. A test arrangement having a ground region in a plane with contacts for contacting the DUT can simulate or approximate such a common use case.

[0051] Furthermore, such an arrangement allows the probe to be positioned behind the ground region, for example within a distance of λ0 / 20 or less from the ground region.

[0052] In a preferred embodiment, the opening is a slot, and the main extension of the probe is orthogonal to the main extension of the slot within a tolerance of + / -20 degrees. Positioning the slot and the probe such that the main extension of the probe is orthogonal to the main extension of the slot within a tolerance of + / -20 degrees can, for example, maximize the received signal transmitted by the antenna of the DUT.

[0053] In a preferred embodiment, the opening is a slot, where the main extension of the slot is shorter than or equal to 0.2 times the free-space wavelength at the center frequency of the frequency range of the antenna of the DUT. A small slot (e.g., with a main extension of 0.2×λ0) can allow the signal to be probed in a manner that the antenna feed impedance is not affected or is not significantly affected.

[0054] In a preferred embodiment, the opening or slot is arranged such that the local current direction in the ground region at the slot position excited by the antenna of the DUT is perpendicular to the main extension of the slot within a tolerance of + / -20 degrees. Positioning the slot such that the local current direction in the ground region at the slot position is substantially perpendicular to the main extension of the slot within a tolerance of + / -20 degrees can, for example, maximize the received signal transmitted by the DUT antenna.

[0055] An embodiment according to the present invention is an automated test equipment (ATE) having a single or multiple sites including a test arrangement, where the test arrangement is adapted to test a DUT including an active circuit (e.g., an MMIC) and an antenna coupled to the circuit.

[0056] The above test arrangement can be integrated in an ATE, which can be used to electronically test a large number of integrated circuits. The ATE can also have multiple sites and / or multiple test arrangements to improve the efficiency and / or speed of the test process.

[0057] The test arrangement described herein can be implemented with a high DUT density at a medium cost and medium size.

[0058] In a preferred embodiment, the DUT includes multiple antennas and one or more active circuits, such as an MMIC.

[0059] In a preferred embodiment, the test arrangement includes one or more ground planes, each ground plane having one or more openings and one or more probes, where each probe can be associated with an antenna of the DUT, or where two or more probes can be associated with some or all of the antennas of the probes to sense, for example, multiple polarizations or circular polarization or elliptical polarization.

[0060] The DUT may include more than one antenna and / or active circuit, which may optionally be probed and / or tested by one or more probes located on the second side of the one or more ground planes.

[0061] In one embodiment, an absorber for the transmitted wireless signal is optionally positioned above the DUT, or on the first side of the DUT opposite the antenna ground, within the radiative near-field distance of the DUT antenna array. Such an absorber allows the ATE structure to be kept compact while avoiding unwanted coupling between the antenna radiator elements of the antenna array and avoiding unwanted degradation of the antenna feed impedance matching condition, i.e., detuning.

[0062] Corresponding methods are created according to other embodiments of the present invention.

[0063] However, it should be noted that these methods are based on the same considerations as the corresponding devices. In addition, for the functions and details described herein with respect to the devices either individually or in combination, these methods can be supplemented by any feature. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Embodiments in accordance with the present application will subsequently be described with reference to the drawings, in which:

[0065] Figure 1 A schematic representation of an embodiment of a test arrangement for testing a device under test including a circuit and an antenna coupled to the circuit is shown;

[0066] Figure 2a A schematic 3D representation of a test arrangement for testing a device under test is shown;

[0067] Figure 2b A schematic 3D representation of an enlarged view of the opening of the test arrangement of FIG. 2A is shown;

[0068] Figure 2c A schematic 3D representation of a device under test including an antenna is shown;

[0069] Figure 2d A schematic 3D representation of a test arrangement coupled to a device under test is shown;

[0070] Figure 3 A schematic representation of an embodiment of a test arrangement for testing a device under test including a circuit and an antenna coupled to the circuit is shown;

[0071] Figure 4a Shows a schematic representation of a conventional embedded wafer-level ball grid array (eWLB) package concept;

[0072] Figure 4b Shows examples of different conventional antenna designs;

[0073] Figure 4c Shows the design of a device under test to be tested using a test arrangement;

[0074] Figure 5 Shows the design of a device under test to be tested using a test arrangement;

[0075] Figure 6 Shows including Figure 1 A schematic representation of an embodiment of an automated test equipment (ATE) including the test arrangement described in Detailed Description

[0076] Different creative embodiments and aspects will be described below. In addition, other embodiments will be defined by the appended claims.

[0077] It should be noted that any embodiment defined by the claims can optionally be supplemented by any details, features, and functions described herein. In addition, the embodiments described herein can be used alone and can also optionally be supplemented by any details, features, and functions included in the claims.

[0078] In addition, it should be noted that the various aspects described herein can be used alone or in combination. Therefore, details can be added to each of the various aspects without adding details to another of the aspects. It should also be noted that the present disclosure explicitly or implicitly describes features that can be used in a test arrangement or an automated test equipment (ATE). Therefore, any feature described herein can be used in the context of a test arrangement or in the context of an automated test equipment.

[0079] In addition, the method-related features and functions disclosed herein can also be used in a device configured to perform such functions. In addition, any feature and function regarding a device disclosed herein can also be used in a corresponding method. In other words, the methods disclosed herein can be supplemented by any feature and function described regarding a device.

[0080] The present invention will be more fully understood from the detailed description given below and the accompanying drawings of the embodiments of the present invention. However, the present invention should not be considered limited to the specific embodiments described, but is only for explanation and understanding.

[0081] According to Figure 1 of the embodiment

[0082] Figure 1 Schematic representation showing an embodiment of a test arrangement 100 for testing a device under test (DUT) 110. The DUT 110 inserted into the test arrangement 100 includes an active circuit 120 such as an MMIC and an antenna 130 coupled to the circuit 120.

[0083] The DUT 110 is positioned in the DUT position 140. The DUT position 140 includes two contact areas 150a, 150b and a ground area 160, where the ground area 160 is located between the contact areas 150a, 150b. The test arrangement 100 can be adapted to contact the DUT 110 in the two contact areas 150a, 150b using spring pins and / or spring-loaded contacts as contact means. The ground area 160 is substantially in the plane having the two contact areas 150a, 150b (or the DUT side surface with the contact means) and between the two contact areas 150a, 150b. The ground area 160 is positioned on a protrusion or raised (e.g., when compared to the surface on which the contact means are arranged) so as to be in the plane having the two contact areas 150a, 150b.

[0084] The antenna ground 160 includes an opening or “minute” opening 170, which is positioned in the central area of the ground area 160. The opening 170 can be a slot, where the main extension of the slot is shorter than or equal to 0.2 times or even 0.1 times the free-space wavelength at the center frequency of the frequency range of the antenna 130 of the DUT 110. The opening 170 (which can be a slot) is arranged, for example, such that the local current direction in the ground area 160 at the position of the slot 170 (excited by the antenna 130 of the DUT 110) is perpendicular or parallel to the main extension of the slot 170 within a tolerance of + / -20 degrees.

[0085] The test arrangement 100 further includes a probe 180. The probe is positioned on the second side of the ground area 160, on the opposite side of the ground area compared to the antenna 130, near the ground area 160 and near the minute opening 170. The probe 180 is positioned in the protrusion in which the ground area 160 is located. The probe 180 can be conductive, and the main extension of the probe 180 can be orthogonal to the main extension of the opening or slot 170, for example, within a tolerance of + / -20 degrees. The distance between the antenna ground 160 and the probe 180 can be equal to or less than λ0 / 20 at the center frequency of the frequency range of the antenna 130 of the DUT110.

[0086] The DUT location 140 of the test arrangement 100 is configured to supply power to the DUT 110 and / or communicate with the active circuit 120 (e.g., MMIC), and the active circuit 120 is coupled to the antenna 130 of the DUT 110 via the contact areas 150a, 150b. The ground area 160 is configured to serve as the antenna ground area for the antenna 130 of the DUT 110, where the main radiation direction 135 of the antenna 130 is, for example, a direction pointing away from the probe 180 and / or away from the ground area 160 from the antenna. The opening 170 and the probe 180 are, for example, positioned in the central area of the ground area 160 of the test arrangement 100. The probe 180 is arranged to couple to the field leaking through the opening 170 in the ground area 160 to detect the signal radiated by the antenna 130 of the DUT 110.

[0087] For example, testing of antennas within a package may require a board ground reflector 160 implemented by the ground area, and the weakly coupled probe 180 can be advantageously mounted below the board ground 160 and coupled through the opening 170 in the board ground 160. The probe 180 is arranged on the second side of the ground area 160 and is adapted to weakly couple to the antenna 130 of the DUT 110 via the opening 170 to detect a signal when the circuit 120 of the DUT 110 feeds the antenna 130 of the DUT 110, and / or to couple a signal to the antenna 130, which signal is fed by the antenna 130 through the circuit 120 of the DUT 110.

[0088] For example, the proposed concept can be applied to a DUT with a planar antenna without a ground for an end-fire radiation dipole structure towards the board plane direction. Here, a probe with a conductive shorting piece can be used to weakly detect the magnetic field in the central symmetry plane of the dipole antenna.

[0089] The proposed concept or test arrangement 100 can also be applied to testing antennas within a package that require an external on-board reflector 160. For example, it is proposed to use such antennas in an embedded wafer-level ball grid array (eWLB) package with a dipole and / or patch antenna, where the circuit board on which the package is mounted provides a metal ground 160 to the antenna radiator 130. For example, the ground area 160 can be electrically coupled to one or more contact devices for contacting the DUT, such that there is a low-impedance connection between the ground area and the DUT when the DUT is inserted into the DUT position. To test such a package including an antenna, the tester must provide a ground 160 at a defined location. The ground area field 160 then becomes part of the antenna 130. The current induced in the ground metal can be detected through the tiny opening 170 in the ground 160 to a test line on the back side. Detection can mean weak detection, i.e., with significant attenuation between the antenna and the probe to avoid the detection interfering with the antenna operation.

[0090] In other words, the proposed new test arrangement and / or test concept is very useful for antennas inside packages that require external on-board reflectors (such as eWLB packages). The tester or test arrangement connects to the test object or DUT and provides a ground for the antenna inside the package of the test object. The tester and / or test arrangement weakly detects the antenna field through a small opening in the provided antenna ground, and this antenna field is proportional (or at least has a fixed relationship) to the radiation field in terms of amplitude and phase. The probe coupling is very weak, so the antenna feed impedance is not affected (or not significantly affected).

[0091] According to the embodiment of FIG. 2

[0092] Figure 2 shows Figure 1 a 3D representation of an embodiment of a test arrangement 200 with and / or without a DUT 210, similar to the test arrangement 100

[0093] Figure 2a Figure 22 shows a test arrangement 200 without a DUT 210. The test arrangement 200 includes contact devices 220, such as spring pins and / or spring-loaded contacts, which can be grouped into one or more contact areas, such as Figure 1 contact areas 150a, 150b in

[0094] For example, the lateral extension of the protrusion can be greater than the free-space wavelength of the signal at the center frequency of the frequency range of the DUT.

[0095] For example, the contact devices 222a - 222d can be arranged near the corners of the protrusion.

[0096] For example, the contact devices 222a - 222d can connect the ground area 230 arranged at the top of the protrusion to the DUT.

[0097] In addition, there are also additional contact devices 220, which are arranged beside (e.g., along a line) one of the edges of the protrusion and can provide power and / or control signals to the DUT, for example.

[0098] Figure 2bA magnified 3D representation of the small opening 240 in the docking area 230 is shown. The small opening 240 is more likely a slit. The main extension of the opening 240 or the slit is, for example, shorter than or equal to 0.2 times the free-space wavelength at the center frequency of the frequency range of the antenna of the DUT 210. Behind the small opening 240 and / or behind the ground area 230, the test arrangement 200 includes a probe 250 similar to the probe 180 in Figure 1 The main extension of the probe 250 is perpendicular to the main extension of the slit 240 within a tolerance of + / - 20 degrees. The probe 250 can be conductive and can form a transmission line or can be part of a transmission line, which can optionally be shorted to the ground area 230 by a conductive strip 260. The probe is within a distance less than λ0 / 4 or less than λ0 / 20 from the slit 240.

[0099] In other words, in the projection perpendicular to the ground area, the probe transmission line forming the probe passes through the slit. On one side of the slit, the probe is shorted to the ground area, and on the other side of the slit, the transmission line is coupled to a circuit for providing a signal to the probe or for evaluating the signal transmitted by the probe.

[0100] Figure 2c A schematic 3D representation of the DUT 210 is shown. The DUT 210 includes a dipole antenna 270 and an embedded wafer-level ball grid array (eWLB) package 280. The DUT 210 includes a planar antenna in a chip-embedded package (such as in the eWLB package 280), where the ground plane or ground area 230 required for the antenna 270 is part of the circuit board on which the module will be mounted and is provided by the ground area 230 when testing the DUT 210.

[0101] Figure 2d A schematic 3D representation of the test arrangement 200 connected to the DUT 210 is shown. The test arrangement 200 and the DUT 210 are connected above the contact devices 220 and 222a - 222d of the test arrangement 200 and above the eWLB package 280 of the DUT 210. The DUT 210 is positioned on the test arrangement 200 such that the dipole antenna 270 of the DUT 210 is positioned near the ground area 230 and above the central area of the ground area 230, for example, above the opening 240 and above the probe 250.

[0102] The proposed test setup and / or concept can be applied to test an in-package antenna that requires an external on-board reflector or ground area 230. Such an antenna is proposed for an eWLB package with a dipole or patch antenna 270, where the circuit board on which the package will be mounted provides a metal ground 230 to the antenna radiator 270. To test such a package including the antenna, the tester or test setup 200 can (and in some cases must) provide a ground at a defined location. This ground field can become part of the antenna 270. The current induced in the ground metal 230 can be probed through a small opening 240 in this ground 230 to a test line on the back side (or can be excited by a signal applied to the probe). Probing can mean weak probing, i.e., with significant attenuation between the antenna 270 and the probe 250 to avoid the probing interfering with the antenna operation.

[0103] Figure 2 shows an eWLB proof-of-concept test simulation setup. The DUT 210 and / or a dummy chip with an in-package dipole antenna 270 require a ground area 230 or ground metal to operate correctly. Figure 2d An in-package dipole antenna 270 with a ground area 230 having a test setup 200 is shown. Figure 2a and Figure 2b A test structure with a connection to the package and a coupling opening 240, which is a rectangular slot in this case, for re-coupling to a probe 250 or microstrip line that is part of the tester or test setup 200 is shown. The microstrip line or probe 250 is arranged to couple to the field leaking through the opening in the ground area to detect the signal radiated by the antenna of the DUT 210.

[0104] Figure 2 shows Figure 1 a schematic 3D representation of the test setup 200 similar to the test setup 100 of Figure 1 . The test setup 200 of Figure 2 is in 3D so that the positions of the components of the test setup 200 or Figure 2a the test setup 100 of Figure 2b are more easily understood. The capabilities of the test setup 200 are illustrated in Figure 2c , where the small opening 240 and the probe 250 behind it are illustrated in close-up in Figure 2d . The DUT 210 that can be connected to the test setup 200 is illustrated and / or shown in

[0105] According to Figure 3 embodiment

[0106] Figure 3 shown with Figure 1An embodiment of a test arrangement 300 similar to the test arrangement 100 of FIG. 1 and the test arrangement 200 of FIG. 2. Similar to Figure 1 the test arrangement 100, the test arrangement 300 includes two contact areas 350a, 350b and a ground area 360 having a small opening 370 in the central area of the ground area 360. The ground area 360 is in the plane of the contact device having the contact areas 350a, 350b. The contact areas 350a, 350b and the ground area 360 are integrated in the DUT location 340.

[0107] The DUT 310 is placed on the upper part of the DUT location 340, and the DUT 310 is coupled to the test arrangement 300 via the contact devices of the contact areas 350a, 350b. At the lower part of the DUT location 340, similar to Figure 1 the test arrangement 100, the probe 380 is positioned in the central area of the ground area 360 near the opening 370. In other words, the DUT is placed on one side of the ground area 360, and the probe is placed on the other opposite side of the ground area.

[0108] The DUT 310 is more detailed than Figure 1 the DUT 110. The DUT 310 includes a redistribution layer 390 and a die 395. The redistribution layer 390 is coupled to the contact areas 350a, 350b of the test arrangement 300 (e.g., via contact balls, which can be part of a ball grid array BGA), and includes an antenna 330 having a main radiation direction 335 that points from the antenna 330 away from the probe 380. The redistribution layer 390 is also connected to an active circuit 320, such as a monolithic microwave integrated circuit (MMIC), which is positioned or packaged in the die, opposite the DUT location 340 (on the side where the redistribution layer avoids the contact device and the ground area 360). The active circuit 320 is also coupled to the antenna 330.

[0109] Similar to Figure 1 the test arrangement 100, the antenna 330 and / or the active circuit 320 are powered by the test arrangement 300 via the contact areas 350a, 350b. The powered antenna 330 of the DUT 310 radiates in the main radiation direction 335 (i.e., away from the ground area 360 or away from the probe 380). The field of the antenna 330 leaks through the opening 370 in the ground area 360 and is detected by the probe 380, which is positioned within a distance preferably not exceeding λ0 / 20 from the antenna ground 360.

[0110] In other words, the conceptual idea of re-coupling to the antenna reactive near-field can be applied to some of the antennas 330 in a test chip embedded package, which may require a metal layer or a ground region 360 on the circuit board for proper operation. Without such a metal ground 360, the antenna 330 is completely detuned, resulting in poor radiation and severe impedance mismatch at the transceiver input / output. For production testing of such modules, the tester or test arrangement 300 can easily provide the required metal ground 360 at an appropriate distance from the module. The small opening 370 in the ground plane 360 provided by the tester and / or test arrangement 300 allows for a well-defined coupling or re-coupling to the transmission line 380 behind the metal ground 360 and is thus used to measure the proper operation of the antenna 330.

[0111] Figure 3 Conceptual diagram showing an eWLB wireless transceiver module with a package-embedded antenna, where the ground plane or ground region 360 required for proper operation of the antenna is part of the tester and / or test arrangement 300.

[0112] Figure 3 Showing Figure 1 A test arrangement 300 similar to the test arrangement 100 of Figure 1 where a class of package-embedded antennas can be tested. The probe and / or transmission line 380 is behind the metal ground shield 360 (e.g., when viewed from the DUT), where the shield is part of the antenna (or becomes part of the antenna when the DUT is placed in the DUT position) and is accessible. Figure 3 The difference between the test arrangement 100 of

[0113] eWLB concept and antenna example according to FIG. 4

[0114] Figure 4 shows a conventional eWLB concept with different antenna examples. Figure 4a Showing a conventional eWLB concept 400, Figure 4b showing different antenna examples, and Figure 4c showing the antenna of the DUT 410.

[0115] Figure 4aShows a traditional eWLB concept 400, where a DUT 410 is coupled to a printed circuit board 440 above two contact regions 450a, 450b and above the wire ball grid array 480 of the DUT. Between the two contact regions 450a and 450b, the printed circuit board 440 includes a ground region 460, which serves as a ground region or as a reflector for the antenna 430 of the DUT 410. The DUT 410 includes an active circuit 420 and an integrated antenna 430. In some cases, the integrated antenna 430 requires a ground metal 460 to operate properly, which indicates that signals are radiated in a direction 435 pointing away from the ground region 460 from the antenna 430.

[0116] The integrated antenna 430 of the DUT 410 can have various antenna designs. Figure 4b Shows some examples of these design concepts: a dipole antenna, an array of two dipole antennas, a CPW patch antenna, and a Vivaldi antenna.

[0117] Figure 4c Shows a DUT 410, which includes a ball grid array 480, an integrated antenna 430, and an active circuit 420, where the antenna 430 is coupled to the active circuit 420, and the active circuit 420 can be connected to other components above the ball grid array 480.

[0118] Figure 4c Shows a DUT 410, which can be tested and / or probed in a test arrangement similar to Figure 1 the test arrangement 100. The DUT 410 is used, for example, in the Figure 4a package-embedded antenna shown in. The antenna 430 to be tested can be, for example, Figure 4b one of the different antenna types described in. The DUT 410 tested in a test arrangement similar to Figure 1 the test arrangement 100 is shown in Figure 4c where the antenna 430 is coupled to the active circuit 420, and the active circuit 420 can be connected to or powered by other components above the ball grid array 480.

[0119] According to Figure 5 the DUT

[0120] Figure 5 Shows a DUT 500 similar to Figure 1 the DUT 110, including a ball grid array package 510, an active circuit 520, and an antenna array 530. The antenna array 530 is coupled to the active circuit 520, and the active circuit 520 can contact other circuit elements through the ball grid array 510. The antenna array 530 is powered by the active circuit 520, and the active circuit 520 is connected to other circuit elements above the ball grid array 510.

[0121] When placed in the DUT position of a test arrangement, an exemplary DUT 500 can be tested in a test arrangement similar to test arrangement 100. An antenna may require a circuit board and / or a metal layer or a ground area on the test arrangement for proper operation. Without such a metal ground, the antenna elements 540 of the antenna array 530 will be completely detuned, resulting in poor radiation and severe impedance mismatch at the transceiver input / output. For production testing of such DUTs, the tester or test arrangement can provide the required metal ground.

[0122] According to Figure 6 automated test equipment

[0123] Figure 6 An embodiment of an automated test equipment (ATE) 800 is shown, the automated test equipment (ATE) 800 including a test arrangement 850 similar to Figure 1 test arrangement 100 and a DUT 860. The test arrangement 850 includes measurement probes 810 and a test fixture 820 or DUT position. The test fixture 820 includes a ground plane or ground area 830. The ground plane serves as a ground area for the antenna array 870 of the DUT 860. The ground plane 830 provided for the DUT antenna by the tester or test arrangement or by the test fixture or by the ATE is in the plane of the surface of the test fixture 820, approximately at the bottom of the contact ball (i.e., the test fixture side), that is to say, if the module or DUT is mounted on a circuit board in a future application scenario, it will be the metallized surface of the circuit board forming the ground plane.

[0124] The DUT 860 is positioned in the test fixture 820 and electrically coupled to the test arrangement 850. The DUT 860 includes a DUT antenna array 870 that can transmit a wireless signal 890 in accordance with the electronic signal 880 of the test arrangement 850. An absorber 840 for the wireless signal 890 to be transmitted is positioned above the DUT 860 opposite the ground area 830, within the radiative near-field distance of the DUT antenna array 870. The absorber allows the ATE structure to be kept compact while avoiding unwanted coupling between the antenna radiator elements of the antenna array 870 and avoiding an undesired degradation of the antenna feed impedance matching condition, also called detuning.

[0125] The antenna elements of the DUT antenna array 870 are probed by probe antennas 810 positioned such that the test fixture 820 is located between the DUT 860 and the probe antennas 810.

[0126] A test arrangement 850 similar to the above test arrangement in the ATE 800 sends an electrical signal 880 to the DUT antenna array 870 of the DUT 860. The DUT antenna array 870 sends a signal 890, which is received by the probe antenna 810 of the test arrangement 850. The received signal is used to test the DUT 860.

[0127] Since Figure 1 the probes of the test arrangement 100 can be placed very close to the DUT, it can be easily integrated into an automated test unit or at the DUT location that can be used to electronically test a large number of integrated circuits.

[0128] References

[0129] [1] A.H. Naqvi and S. Lim, “Review of recent phased arrays for millimeter-wave wireless communication,” Sensors, vol. 18, no. 10, Oct. 2018, pp. 3194 / 1 - 31.

[0130] [2] M.A. Mow, B.H. Noori, M. Pascolini, X. Han, V.C. Lee, M.-J. Tsai, and S. Paulotto, “Electronic device with millimeter wave antenna arrays,” U.S. Patent Application US2018 / 0090816A1, Mar. 29, 2018.

[0131] [3] X. Gu, D. Liu, C. Baks, O. Tageman, B. Sadhu, J. Hallin, L. Rexberg, and A. Valdes-Garcia, “A multilayer organic package with 64 dual-polarized antennas for 28GHz 5G communication,” in IEEE MTT-S International Microwave Symposium (IMS), June 2017, pp. 1899 - 1901.

[0132] [4] S. Shahramian, M. J. Holyoak, and Y. Baeyens, “A 16 - element W - band phased - array transceiver chipset with flip - chip PCB integrated antennas for multi - gigabit wireless data links,” IEEE Trans. Microwave Theory Techniques, vol. 66, no. 7, July 2018, pp. 3389 - 3402.

[0133] [5] M.-C. Huynh, “System and method for testing radio frequency wireless signal transceivers using wireless test signals,” U.S. Patent 9 774 406, Sep. 26, 2017.

[0134] [6] A. Pabst and C. Rowell, “Test system and test method,” U.S. Patent 9954 279, Apr. 24, 2018.

[0135] [7] J. Kyrolainen and P. Kyosti, “Systems and methods for performing multiple input, multiple output (MIMO) over - the - air testing,” U.S. Patent 10 033 473, Jul. 24, 2018.

[0136] [8] J. Peeters, “Production test of cm and mmWave devices,” in Proc. Salland Test Technology Symposium, Zwolle, Netherlands, Sep. 2018, [Online]. Available: https: / / www.salland.com / wp - content / uploads / 2018 / 09 / 11 - SE - Symposium - Jan - Peeters - Xcerra.pdf.

[0137] [9]G.Schuppener and R.F.Payne,“Interface between an integratedcircuitand a dielectric waveguide using a dipole antenna,a reflector and aplurality of director elements,”U.S.Patent 9 300 024,Mar.29,2016.

[0138]

[10] M.Wojnowski,C.Wagner,R.Lachner,J. G.Sommer,and K.Pressel,“A77-GHz SiGe single-chip four-channel transceiver module with integratedantennas in embedded wafer-level BGA package,”in IEEE 62nd ElectronicComponents Technology Conf.,San Diego,CA,June 2012,pp.1027-1032.

[0139]

[11] M.Wojnowski,C.Wagner,R.Lachner,J. G.Sommer,K.Pressel,“A 77-GHz SiGe single-chip four-channel transceiver module with integrated antennasin embedded wafer-level BGA package,”IEEE 62nd Electronic ComponentsTechnology Conf.,June 2012.

[0140]

[12] I. Nasr, R. Jungmaier, A. Baheti, D. Noppeney, J. S. Bal, M. Wojnowski, E. Karagozler, H. Raja, J. Lien, I. Poupyrev, S. Trotta, “A highly integrated 60 GHz 6-channel transceiver with antenna in package for smart sensing and short-range communications,” IEEE Journal Solid-State Circuits, vol. 51, no. 9, Sep. 2016, pp. 2066-2076.

Claims

1. A test arrangement (100, 200, 300, 850) for testing a device under test DUT (110, 210, 310, 410, 860), the device under test including a circuit (120, 320, 420, 520) and an antenna (130, 270, 330, 430, 530, 870) coupled to the circuit, wherein the test arrangement includes a DUT position (140, 340, 820) and probes (180, 250, 380, 810), wherein the test arrangement includes a ground region (160, 230, 360, 460, 830), the ground region being configured to serve as an antenna ground region for the antenna of the DUT, wherein the ground region includes an opening (170, 240, 370), wherein the DUT position is on a first side of the ground region, and wherein the probes are arranged on a second side of the ground region and are adapted to be coupled to the antenna of the DUT via the opening, so as to detect a signal (890) when the circuit of the DUT feeds the antenna of the DUT and / or so as to couple a signal fed from the antenna to the circuit of the DUT to the antenna.

2. The test arrangement according to claim 1, wherein the probes are conductive.

3. The test arrangement according to claim 1 or 2, wherein the probes form a transmission line or are part of a transmission line.

4. The test arrangement according to any one of claims 1 to 3, wherein the probes are in the reactive near-field region of the antenna.

5. The test arrangement according to any one of claims 1 to 4, wherein the ground region and / or the probes are integrated into the DUT position.

6. The test arrangement according to any one of claims 1 to 5, wherein the probes are arranged to be coupled to a field leaking through the opening in the ground region to detect a signal radiated by the antenna of the DUT in the direction of the first side of the ground region.

7. The test arrangement according to any one of claims 1 to 6, wherein the opening and the probes are located in a central region of the ground region, the ground region serving as an antenna ground region for a patch antenna of the DUT.

8. The test arrangement according to any one of claims 1 to 7, wherein the DUT position includes at least one contact region (150a, 150b, 350a, 350b, 450a, 450b) in which contact means (220, 222a - 222d, 480, 510) for contacting the DUT are arranged, and wherein the ground region behind which the probes are arranged is located next to the contact region, such that when the DUT is placed in the DUT position, the contacts of the DUT contact the contact means, and such that when the DUT is placed in the DUT position, the integrated antenna of the DUT is near the ground region.

9. The test arrangement according to any one of claims 1 to 8, The ground region behind which the probe is arranged is arranged between two contact regions of the test arrangement associated with the same DUT, such that when the DUT is placed in the DUT position, the integrated antenna of the DUT arranged between the two contact regions of the DUT is in the vicinity of the ground region behind which the probe is arranged.

10. The test arrangement according to one of claims 1 to 9, wherein the ground region behind which the probe is arranged is in a plane having contacts for contacting the DUT.

11. The test arrangement according to one of claims 1 to 10, wherein the opening is a slot, and the main extension of the probe is orthogonal or parallel to the main extension of the slot within a tolerance of + / - 20 degrees.

12. The test arrangement according to one of claims 1 to 11, wherein the opening is a slot, and wherein the main extension of the slot is shorter than or equal to 0.2 times the free space wavelength at the center frequency of the frequency range of the antenna of the DUT.

13. The test arrangement according to one of claims 1 to 12, wherein the opening or slot is arranged such that the direction of the local current in the ground region at the position of the slot excited by the antenna of the DUT is perpendicular to the main extension of the slot within a tolerance of + / - 20 degrees.

14. An automated test equipment ATE having a single site or multiple sites including the test arrangement according to any one of claims 1 to 13, wherein the test arrangement is adapted to test a DUT, the DUT including a circuit and an antenna coupled to the circuit.

15. The ATE according to claim 14, wherein the DUT includes a plurality of antennas and one or more circuits.

16. The ATE according to claim 15, wherein the test arrangement includes one or more ground planes, each ground plane having one or more openings and one or more probes respectively.

17. The ATE according to one of claims 14 to 16, wherein the test arrangement includes absorber material (840) in the radiative near-field region or far-field region of the antenna of the DUT on the first side of the DUT, the first side of the DUT being opposite to the antenna ground side of the DUT.

18. A method for testing a device under test DUT, the DUT including a circuit and an antenna coupled to the circuit, wherein the test arrangement includes a ground region, the ground region serving as an antenna ground region for the antenna of the DUT, wherein the ground region includes an opening, wherein a probe is coupled to the antenna of the DUT via the opening.

19. The method for testing a device under test DUT according to claim 18, wherein the probe is coupled to the antenna of the DUT via the opening, so as to detect signals when the circuit of the DUT feeds the antenna of the DUT and / or so as to couple the signals fed by the antenna to the circuit of the DUT to the antenna.

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