Patent Publication Number: US-2021190821-A1

Title: Dielectric resonating test contactor and method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent application claims the benefit of priority of U.S. application Ser. No. 62/950,755, filed Dec. 19, 2019, and of U.S. application Ser. No. 62/989,278, filed Mar. 13, 2020, which applications are herein incorporated by reference. 
    
    
     BACKGROUND 
     A test contactor included in integrated circuit test systems couples a test signal from a test signal source to an integrated circuit under test. A typical test contactor includes a test probe embedded in a material having a single dielectric constant. The bandwidth of these test contactors is insufficient to transmit test signals at the frequencies required to test many high-frequency analog integrated circuits or the data rates required to test many high-frequency digital integrated circuits. For these and other reasons there is a need for the subject matter of the present disclosure. 
     SUMMARY 
     Consistent with the disclosed embodiments, a test contactor is disclosed. The test contactor comprises two or more dielectric layers and a test probe embedded in the two or more dielectric layers. The test probe traverses the two or more dielectric layers. The test probe to include an input signal port and an output signal port and the test probe to transmit a test signal from the input signal port to the output signal port. In some embodiments, one of the two or more dielectric layers includes a material having a low dielectric constant. In some embodiments, the test probe includes a ground-signal probe contact configuration. 
     Consistent with the disclosed embodiments, a system for testing an integrated circuit is disclosed. The system comprises a test signal source to provide a test signal, a test station for mounting the integrated circuit, and a test contactor. The test contractor includes two or more dielectric layers and a test probe. The test probe is embedded in the two or more dielectric layers and traverses the two or more dielectric layers. The test probe includes an input signal port and an output signal port, and the test probe to transmit a test signal from the input signal port to the output signal port. In some embodiments, one of the two or more dielectric layers includes a material having a medium or high dielectric constant. In some embodiments, the test probe includes a ground-signal probe contact configuration. 
     Consistent with the disclosed embodiments, a test contactor is disclosed. The test contactor comprises a dielectric stack, a dielectric layer, and a test probe. The dielectric layer includes a first dielectric layer, a second dielectric layer, and a third dielectric layer located between the first dielectric layer and the second dielectric layer. The test probe is embedded in the dielectric stack and traverses the dielectric stack from the first dielectric layer to the second dielectric layer. The test probe includes an input signal port and an output signal port. In operation, the test probe transmits a test signal from the input signal port to the output signal port. In some embodiments, the first dielectric layer includes a first dielectric material having a first dielectric constant, the second dielectric layer includes a second dielectric material having a second dielectric constant, and the third dielectric layer includes a third dielectric material having a third dielectric constant. In some embodiments, the third dielectric constant is less than the first dielectric constant and the second dielectric constant. In some embodiments, the first dielectric constant is a medium or high dielectric constant. In some embodiments, the test probe includes a ground-signal-ground probe contact geometry. In some embodiments, the test contactor further comprises a fourth dielectric layer located between the first dielectric layer and the third dielectric layer, and a fifth dielectric layer located between the second dielectric layer and the third dielectric layer. In some embodiments, the fourth dielectric layer includes a material having a low dielectric constant. In some embodiments, the third dielectric layer includes a material having a medium or high dielectric constant. 
     Consistent with the disclosed embodiments, a test contactor is disclosed. The test contactor comprises a dielectric assembly including a first dielectric stack and a second dielectric stack, the second dielectric stack having at least three dielectric layers. The test contactor comprises a first test probe embedded in the first dielectric stack. The test contactor comprises a second test probe embedded in the second dielectric stack. In some embodiments, at least one of the three dielectric layers includes a material having a medium or high dielectric constant. In some embodiments, the first test probe includes a ground-signal probe contact configuration. In some embodiments, at least one of the three dielectric layers includes a material having a low dielectric constant. In some embodiments, the second test probe includes a ground-signal-signal-ground probe contact configuration. In some embodiments, the first test probe includes a test probe pitch of between about twenty-five microns and about one thousand five hundred microns. 
     Consistent with the disclosed embodiments, a method for manufacturing a test contactor is disclosed. The method comprises forming a dielectric stack including at least three dielectric layers. The method comprises integrating a test probe into the dielectric stack. In some embodiments, integrating the test probe into the dielectric stack comprises machining the dielectric stack to form a space for the test probe and inserting the test probe into the space. In some embodiments, forming the dielectric stack including at least three dielectric layers comprises selecting at least one dielectric layer of the three dielectric layers to have a low dielectric constant. 
     Consistent with the disclosed embodiments, a system for testing an integrated circuit is disclosed. The system comprises a test signal source to provide a test signal, a test station for mounting the integrated circuit, a test contactor, and a test probe to couple the test signal to the integrated circuit. The dielectric stack includes a first dielectric layer, a second dielectric layer, and a third dielectric layer located between the first dielectric layer and the second dielectric layer. In operation, the test probe couples the test signal to the integrated circuit. The test probe is embedded in the dielectric stack and traverses the dielectric stack from the first dielectric layer to the second dielectric layer. The test probe includes an input signal port and an output signal port and in operation transmits a test signal from the input signal port to the output signal port. In some embodiments, the third dielectric layer includes a material having a medium or high dielectric constant. In some embodiments, the test probe includes a ground-signal probe contact configuration. The test system further comprises a fourth dielectric layer located between the first dielectric layer and the third dielectric layer and a fifth dielectric layer located between the second dielectric layer and the third dielectric layer. In some embodiments, the test signal includes a frequency of between about dc and about one hundred gigahertz. 
     Consistent with the disclosed embodiments, a method for testing an integrated circuit is disclosed. The method comprises mounting the integrated circuit on a test station. The method comprises generating a test signal. The method comprises coupling the test signal through a test probe embedded in a dielectric stack, including at least three dielectric layers, to the integrated circuit. In some embodiments, the integrated circuit generates the test signal. In some embodiments, generating the test signal comprises generating the test signal with a frequency of between about dc and about one hundred gigahertz. 
     Consistent with the disclosed embodiments, a system for testing an integrated circuit is disclosed. The system includes a test signal source to provide a test signal, a test station for mounting the integrated circuit, and a test contactor. The test contactor further comprises two or more dielectric layers, and a test probe embedded in the two or more dielectric layers. The test probe traverses the two or more dielectric layers. The test probe to include an input signal port and an output signal port and the test probe to transmit the test signal from the input signal port to the output signal port. In some embodiments, one of the two or more dielectric layers includes a material having a medium or high dielectric constant. In some embodiments, the test probe includes a ground-signal probe contact configuration. 
     Consistent with the disclosed embodiments, a test contactor is disclosed. The test contactor includes a first plate, a second plate, and one or more dielectric layers formed between the first plate and the second plate. The test probe is embedded in the first plate. The test probe is embedded in the one or more dielectric layers. The test probe is embedded in the second plate. The test probe traverses the first plate, the one or more dielectric layers, and the second plate. The test probe to include an input signal port and an output signal port and the test probe to transmit a test signal from the input signal port to the output signal port. In some embodiments, one of the one or more dielectric layers includes a material having a low dielectric constant. In some embodiments, the test probe includes a ground-signal probe contact configuration. 
     Consistent with the disclosed embodiments a test contactor is disclosed. The test contact includes a dielectric material stack up engineered for optimized radio frequency performance, mechanical robustness, and manufacturing efficiency. 
     Consistent with the disclosed embodiments a test contactor is disclosed. The test contactor includes a dielectric material stack up including a plurality of dielectric materials, each of the plurality of dielectric materials having a thickness engineered for optimized radio frequency performance, mechanical robustness, and manufacturing efficiency. 
     Consistent with the disclosed embodiments, a design process for a contactor including two or more dielectric layers and having a contactor radio frequency performance, given a radio frequency performance design goal is disclosed. The design process includes selecting a hole diameter for a probe traversing the two or more dielectric layers and stopping the design process if the contactor radio frequency performance meets the radio frequency performance design goal. The design process includes selecting a new material and a new thickness for one of the two or more dielectric layers and stopping the design process if the contactor radio frequency performance meets the radio frequency performance design goal. And the design process includes adding a new dielectric layer to the contactor, the new dielectric layer having a new dielectric layer dielectric constant and a new dielectric layer thickness, and stopping the design process if the radio frequency performance of the contactor meets the radio frequency performance design goal. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  shows a schematic illustration of a test contactor including a dielectric stack and a test probe embedded in the dielectric stack in accordance with some embodiments of the present disclosure; 
         FIG. 1B  shows a schematic illustration of the test contactor shown in  FIG. 1A  and further including a fourth dielectric layer and a fifth dielectric layer in accordance with some embodiments of the present disclosure; 
         FIG. 2  shows a schematic illustration of a test contactor in accordance with some embodiments of the present disclosure; 
         FIG. 3  shows a flow diagram of a method for manufacturing a test contactor in accordance with some embodiments of the present disclosure; 
         FIG. 4  shows a block diagram of a system for testing an integrated circuit in accordance with some embodiments of the present disclosure; 
         FIG. 5  shows a flow diagram of a method for testing an integrated circuit in accordance with some embodiments of the present disclosure; 
         FIG. 6  shows a graph of predicted insertion loss for a single dielectric contactor and predicted insertion loss for an exemplary contactor in accordance with some embodiments of the present disclosure; 
         FIG. 7  shows a graph of predicted return loss for a single dielectric contactor and predicted return loss for an exemplary contactor in accordance with some embodiments of the present disclosure; 
         FIG. 8A  shows an illustration of a graph of probe return loss (frequency domain plot) in accordance with some embodiments of the present disclosure; 
         FIG. 8B  shows an illustration of a graph of probe impedance (time domain plot) in accordance with some embodiments of the present disclosure; 
         FIG. 9  shows an illustration of signal pins and ground pins embedded in a dielectric for an exemplary contactor in accordance with some embodiments of the present disclosure; 
         FIG. 10  shows an illustration of a test contactor including two or more dielectric layers and a test probe embedded in the two or more dielectric layers in accordance with some embodiments of the present disclosure; 
         FIG. 11  shows a system for testing an integrated circuit in accordance with some embodiments of the present disclosure; and 
         FIG. 12  shows a schematic illustration of a test contactor including a first plate, a second plate, one or more dielectric layers and a test probe embedded in the first plate, the second plate, and the one or more dielectric layers in accordance with some embodiments of the present disclosure. 
     
    
    
     DESCRIPTION 
     Reference will now be made in detail to the exemplary embodiments of the present disclosure described below and illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout to refer to same or like parts. 
     While the present invention is described herein with reference to illustrative embodiments for particular applications, it should be understood that the invention is not limited thereto. Those having ordinary skill in the art and access to the teachings provided herein will recognize additional modifications, applications, embodiments, and substitution of equivalents, that all fall within the scope of the disclosure. Accordingly, the disclosure is not to be considered as limited by the foregoing or following descriptions. 
       FIG. 1A  shows a schematic illustration of a test contactor  100  including a dielectric stack  102  and a test probe  104  embedded in the dielectric stack  102  in accordance with some embodiments of the present disclosure. The dielectric stack  102  includes a first dielectric layer  106 , a second dielectric layer  108 , and a third dielectric layer  110 . The third dielectric layer  110  is located between the first dielectric layer  106  and the second dielectric layer  110 . A low dielectric constant is between about one and about three. A medium dielectric constant is between about three and about six. A high dielectric constant is greater than about six. Materials having a medium or high dielectric constant are used in the fabrication of the first dielectric layer  106 , the second dielectric layer  108  and the third dielectric layer  110 . 
     In some embodiments, machinable ceramics are used in the fabrication of one or more of the first dielectric layer  106 , the second dielectric layer  108 , and the third dielectric layer  110 . A test probe includes one or more signal conductors and one or more ground conductors to deliver a test signal to an integrated circuit under test. The test probe  104  includes an input signal port  112  and an output signal port  114 . Those skilled in the art will appreciate that the input signal port  112  and the output signal port  114  may include both signal conductors and ground conductors. The test probe  104  traverses the dielectric stack  102  from the first dielectric layer  106  to the second dielectric layer  108 . The test probe  104  is not limited to a particular probe contact configuration. In some embodiments, the test probe  104  has a ground-signal-ground probe contact configuration. In operation, the test probe  104  transmits a test signal from the input signal port  112  to the output signal port  114 . 
     In the test contactor  100  shown in  FIG. 1A , the first dielectric layer  106  includes a first dielectric material having a first dielectric constant, the second dielectric layer  108  includes a second dielectric material having a second dielectric constant, and the third dielectric layer  110  includes a third dielectric material having a third dielectric constant. A dielectric constant is a numerical measure of the ability of a material to isolate charges from one another and is representative of the permittivity of a substance when compared to a vacuum. In some embodiments, the third dielectric constant is less than the first dielectric constant and the second dielectric constant. In some embodiments, the first dielectric constant is a medium dielectric constant. A medium dielectric constant has a value of between about three and about six. In some embodiments, the electrical performance of the test contactor  100  is optimized at various pitches of the test probe  104  to use thicker or thinner materials having different dielectric constant for the first dielectric layer  106 , the second dielectric layer  108 , and the third dielectric layer  110 . 
       FIG. 1B  shows a schematic illustration of the test contactor  100  shown in  FIG. 1A  and further including a fourth dielectric layer  116  and a fifth dielectric layer  118  in accordance with some embodiments of the present disclosure. The fourth dielectric layer  116  is located between the first dielectric layer  106  and the third dielectric layer  110 . The fifth dielectric layer  118  is located between the second dielectric layer  108  and the third dielectric layer  110 . In some embodiments, the fourth dielectric layer  116  includes a material having a low dielectric constant. A low dielectric constant has a value of between about one and about three. In some embodiments, the fifth dielectric layer  118  includes a material having a medium or high dielectric constant. A medium dielectric constant has a value of between about three and about six. A high dielectric constant has a value of greater than about six. 
     The dielectric stack  102  includes a distance  120  between the first dielectric layer  106  and the second dielectric layer  108 . The distance  120  is probe dependent and pitch dependent. In some embodiments, the distance  120  is between about one-eighth and about seven-eighths of a wavelength of the test signal transmitted by the test contactor  100 . 
     In some embodiments, a test contactor includes a dielectric material stack up engineered for optimized radio frequency performance, mechanical robustness, and manufacturing efficiency either separately or combined. The dielectric material stack up is engineered for optimized radio frequency performance by matching the impedance of the contactor to the specification for a device to be tested, providing a low insertion loss, and providing low reflection. The dielectric material stack up is engineered for mechanic robustness by engineering the dielectric material stack up for increased stiffness, wear resistance, durability, and life-time. The dielectric material stack up is engineered for manufacture efficiency by engineering for through put, cost, and lead time. 
     In some embodiments, a test contactor includes a dielectric material stack up including a plurality of dielectric materials, each of the plurality of dielectric materials having a thickness engineered for optimized radio frequency performance, mechanical robustness, and manufacturing efficiency either separately or combined. The plurality of dielectric materials is engineered for optimized radio frequency performance by matching the impedance of the contactor to the specification for a device to be tested, providing a low insertion loss, and providing low reflection. The plurality of dielectric materials is engineered for mechanic robustness by engineering the dielectric material stack up for increased stiffness, wear resistance, durability, and life-time. The plurality of dielectric materials is engineered for manufacture efficiency by engineering for through put, cost, and lead time. 
       FIG. 2  shows a schematic illustration of a test contactor  200  in accordance with some embodiments of the present disclosure. The test contactor  200  includes a dielectric assembly  202 , a first test probe  204 , and a second test probe  206 . The dielectric assembly  202  includes a first dielectric stack  208  and a second dielectric stack  210 . The first dielectric stack  208  is formed from a single dielectric material. 
     The first test probe  204  is embedded in the first dielectric stack  208 . In some embodiments, the first test probe  204  includes a ground-signal probe contact configuration. The first test probe  204  includes a test probe pitch  211 . The test probe pitch is the distance between the conductors in a test probe, for example, the distance between a ground conductor and a signal conductor in a ground-signal test probe contact configuration. The test probe pitch  211  is not limited to a particular distance. In some embodiments, the test probe pitch  211  is between about twenty-five microns and about one thousand five hundred microns. In some embodiments, the test probe pitch  211  is between about twenty-five microns and about five hundred microns. In some embodiments, the test probe pitch  211  is between about five hundred microns and about one thousand microns. In some embodiments, the test probe pitch  211  is between about one thousand microns and about one thousand five hundred microns. 
     The second test probe  206  is embedded in the second dielectric stack  210 . In some embodiments, the second test probe  206  includes a ground-signal-ground probe contact configuration. 
     The second dielectric stack has at least three dielectric layers  212 , including a first dielectric layer  214 , a second dielectric layer  216 , and a third dielectric layer  218 . In some embodiments, at least one of the at least three dielectric layers  212 , for example, the first dielectric layer  214 , includes a material having a medium or high dielectric constant. A medium dielectric constant has a value of between about three and about six. A high dielectric constant has a value of greater than about six. In some embodiments, at least one of the three dielectric layers  212  includes a material having a low dielectric constant. A low dielectric constant is a dielectric constant of between about one and about three. 
       FIG. 3  shows a flow diagram of a method  300  for manufacturing a test contactor in accordance with some embodiments of the present disclosure. The method  300  includes forming a dielectric stack including at least three dielectric layers (block  302 ) and integrating a test probe into the dielectric stack (block  304 ). In some embodiments, integrating the test probe into the dielectric stack includes machining the dielectric stack to form a space for the test probe and inserting the test probe into the space. In some embodiments, forming the dielectric stack including at least three dielectric layers comprises selecting at least one dielectric layer of the three dielectric layers to have a low dielectric constant. A low dielectric constant is a dielectric constant having a value of between about one and about three. 
       FIG. 4  shows a block diagram of a system  400  for testing an integrated circuit in accordance with some embodiments of the present disclosure. The system  400  includes a test signal source  402  to provide a test signal, a test station  404  for mounting the integrated circuit, and a test contactor  100  (shown in  FIG. 1A ). In some embodiments, the third dielectric layer  110  (shown in  FIG. 1A ) includes a material having a medium dielectric constant. A medium dielectric constant is a dielectric constant between about two and about four. In some embodiments, the test probe  104  (shown in  FIG. 1A ) includes a ground-signal probe contact configuration. In some embodiments, the test contactor  100  (shown in  FIG. 1A ) further includes a fourth dielectric layer  116  (shown in  FIG. 1B ) located between the first dielectric layer  106  (shown in  FIG. 1B ) and the third dielectric layer  110  (shown in  FIG. 1B ) and a fifth dielectric layer  118  (shown in  FIG. 1B ) located between the second dielectric layer  108  (shown in  FIG. 1B ) and the third dielectric layer  110  (shown in  FIG. 1B ). In some embodiments, the test signal includes a frequency of between about dc and about one hundred gigahertz. In some embodiments, the test signal includes a frequency of between about dc and about thirty gigahertz. In some embodiments, the test signal includes a frequency of between about thirty gigahertz and about forty-five gigahertz. In some embodiments, the test signal includes a frequency of between about forty-five gigahertz and about sixty-five gigahertz. In some embodiments, the test signal includes a frequency of between about sixty-five gigahertz and about one hundred gigahertz. 
       FIG. 5  shows a flow diagram of a method  500  for testing an integrated circuit in accordance with some embodiments of the present disclosure. The method includes mounting the integrated circuit on a test station (block  502 ), generating a test signal (block  504 ), and coupling the test signal through a test probe embedded in a dielectric stack, including at least three dielectric layers, to the integrated circuit (block  506 ). In some embodiments, the integrated circuit generates the test signal. In some embodiments, generating the test signal comprises generating the test signal with a frequency of between about dc and about one hundred gigahertz. 
       FIG. 6  shows a graph  600  of predicted insertion loss obtained from a simulation for a single dielectric contactor  602  and predicted insertion loss obtained from a simulation for an exemplary contactor  604  in accordance with the present disclosure. Insertion loss is the loss of signal power resulting from the insertion of a contactor in the path of the test signal. As can be seen in the graph  600 , the insertion loss for the exemplary contactor  604  is down 1 dB at about eighty-six megahertz, while the insertion loss for the single dielectric contactor  602  is down 1 dB at about thirty-one gigahertz. A loss of 1 dB is the standard for acceptable performance of a test contactor in the semiconductor test equipment industry. Thus, there is a significant and unexpected bandwidth increase of about fifty-five gigahertz for the exemplary contactor  604  in accordance with the present disclosure when compared to the single dielectric contactor  602 . 
       FIG. 7  shows a graph  700  of predicted return loss obtained form a simulation for a single dielectric contactor  702  and predicted return loss obtained from a simulation for an exemplary contactor  704  in accordance with the present disclosure. Return loss is the ratio of the reflected power to the incident power. As can be seen in the graph  700 , the return loss for the exemplary contactor  704  is down 10 dB at about eighty-nine gigahertz, while the return loss for the single dielectric contactor  702  is down 10 dB at about thirty-six gigahertz. A return loss of 10 dB is the standard for acceptable performance of a test contactor in the semiconductor test equipment industry. Thus, there is a significant and unexpected bandwidth improvement of about fifty-three gigahertz for the exemplary contactor  704  when compared to the single dielectric contactor  702 . 
     Comparative predictive data obtained from a simulation for the digital performance of a single dielectric contactor with the digital performance of an exemplary contactor in accordance with the present disclosure was also developed. An eye diagram was generated and distortion of a digital input signal having a data rate of fifty-six gigabits per second and a rise time of four picoseconds was extracted from the eye diagram. For the single dielectric contactor, the eye signal-to-noise ratio was 21.77, while for the exemplary contactor of the present disclosure the eye signal-to-noise ratio was 59.64. For the single dielectric contactor, the ten-to-ninety percent rise time was 10.03 picoseconds, while for the exemplary contactor of the present disclosure the ten-to-ninety percent rise time was 7.77 picoseconds. For the single dielectric contactor, the eye jitter was 0.4991 RMS, while for the exemplary contactor of the present disclosure of contactor eye jitter was 0.0930 RMS. For each measure of performance, the exemplary contactor of the present disclosure showed a significant and unexpected performance improvement when compared to a single dielectric contactor. 
       FIG. 8A  shows an illustration of a graph of probe return loss (frequency domain plot) in accordance with some embodiments of the present disclosure.  FIG. 8B  shows an illustration of a graph of probe impedance (time domain plot) in accordance with some embodiments of the present disclosure. As can be seen in  FIG. 8A  and  FIG. 8B , the calculated time domain impedance response appears to be high for 50 ohms, however, the unexpected return loss seen by the contactor provides improved performance at a higher frequency than a current contactor design. 
       FIG. 9  shows an illustration of signal pins  902  and ground pins  904  embedded in a dielectric  906  for an exemplary contactor  900  in accordance with some embodiments of the present disclosure. The pitch (distance between signal pins  902  and ground pins  904 ) is not limited to a particular value. The height of the signal pins  902  (distance from one end of the pin to the other) and the ground pins  904  (distance from one end of the pin to another) is not limited to a particular value. 
       FIG. 10  shows an illustration of a test contactor  1000  including one or more dielectric layers, dielectric layer  1004  and dielectric layer  1005 , and a test probe  1006  embedded in the one or more dielectric layers in accordance with some embodiments of the present disclosure. The test probe  1006  embedded in the one or more dielectric layers and traversing the one or more dielectric layers, the test probe  1006  to include an input signal port  1008  and an output signal port  1010  and the test probe  1006  to transmit a test signal from the input signal port  1008  to the output signal port  1010 . In some embodiments, one of the one or more dielectric layers includes a material having a low dielectric constant. In some embodiments, the test probe  1006  includes a ground-signal probe contact configuration. In some embodiments, one of the one or more dielectric layers includes a material having a medium or high dielectric constant. In some embodiments, the test probe  1006  includes a ground-signal probe contact configuration. The cross-section of the pins in the probe including both the barrels and the plungers are selected to achieve the desired impedance of the test contactor  1000 . 
     The stack-up of the test contactor  1000  is related to the frequency of interest (frequency=1/wavelength). The thickness and order of dielectric layer stack-up includes one or more dielectric layers. The reference equation f_resonance=1/(2π√LC) is used in the design of the test contactor  1000 . As used herein, f_resonance is the center frequency of the interested band, and L and C are the parasitic inductance and capacitance in the contactor signal path. Through adjusting dielectric material and dielectric layer stack-up, the resonance frequency, contactor frequency bandwidth and probe inductance are determined. 
       FIG. 11  shows a system  1100  for testing an integrated circuit in accordance with some embodiments of the present disclosure. The system  1100  includes a test signal source  1102  to provide a test signal  1104 , a test station  1106  for mounting the integrated circuit  1108  or other device under test, and a test contactor  1000 . In operation, in some embodiments, the test contactor  1000 , as shown in  FIG. 9 , transmits the test signal  1104  from the test signal source  1102  to the integrated circuit  1108 . In some embodiments, the test signal source is configured to receive a signal from the integrated circuit  1108 . 
       FIG. 12  shows a schematic illustration of a test contactor  1200  including a first plate  1202 , a second plate  1204 , one or more dielectric layers  1206  and a test probe  1208  embedded in the first plate  1202 , the second plate  1204 , and the one or more dielectric layers  1206  in accordance with some embodiments of the present disclosure. The one or more dielectric layers  1206  are formed between the first plate  1202  and the second plate  1204 . The test probe  1208  traverses the first plate  1202 , the one or more dielectric layers  1206 , and the second plate  1204 . The test probe  1208  to include an input signal port  1210  and an output signal port  1212  and the test probe  1208  to transmit a test signal from the input signal port  1210  to the output signal port  1212 . In some embodiments, the one of the one or more dielectric layers  1206  includes a material having a low dielectric constant. In some embodiments, the test probe  1208  includes a ground-signal-ground probe contact configuration. In some embodiments, the one or more dielectric layers  1206  is the dielectric stack  102  (shown in  FIG. 1A ). In some embodiments, the first plate  1202  is a probe retention plate. In some embodiments, the second plate  1204  is a probe alignment plate. 
     In some embodiments, a design process for a contactor including two or more dielectric layers and having a contactor radio frequency performance, given a radio frequency performance design goal, includes selecting a hole diameter for a probe traversing the two or more dielectric layers and stopping the design process if the contactor radio frequency performance meets the radio frequency performance design goal, selecting a new material and a new thickness for one of the two or more dielectric layers and stopping the design process if the contactor radio frequency performance meets the radio frequency performance design goal, and adding a new dielectric layer to the contactor, the new dielectric layer having a new dielectric layer dielectric constant and a new dielectric layer thickness, and stopping the design process if the radio frequency performance of the contactor meets the radio frequency performance design goal. 
     Reference throughout this specification to “an embodiment,” “some embodiments,” or “one embodiment.” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, the appearances of the phrases such as “in some embodiments,” “in one embodiment,” or “in an embodiment,” in various places throughout this specification are not necessarily referring to the same embodiment of the present disclosure. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments. 
     Although explanatory embodiments have been shown and described, it would be appreciated by those skilled in the art that the above embodiments cannot be construed to limit the present disclosure, and changes, alternatives, and modifications can be made in the embodiments without departing from spirit, principles and scope of the present disclosure.