TWI395968B - High frequency characteristic measurement of the straight through the calibration substrate - Google Patents

Description

Straight-through correction substrate for high-frequency characteristic measurement

The present invention relates to a through-correction substrate, and more particularly to a through-correction substrate for high-frequency characteristic measurement.

Instruments commonly used for measuring the electrical characteristics of high-frequency connectors include Time Domain Reflectrometer (TDR) and Vector Network Analyzer (VNA). The vector network analyzer measures the device under test (DUT) in the frequency domain, and treats the object to be tested as an entire network system, and measures the overall power-through of the object to be tested. The response of the Transmitted Coefficient and the Reflected Coefficient to evaluate the high frequency electrical characteristics of the object under test.

Since the instrument and the test fixture must be calibrated before using the vector network analyzer, although the measurement procedure is cumbersome, the result is more accurate. The main key technology for measuring with the network analyzer is the calibration. For the standard test piece, the SLOT method can be used to correct the effect of the instrument and the test fixture, and the measurement can be accurately measured.

The so-called SLOT method refers to short-circuit, load-circuit, open-circuit, and thru-circuit standard impedance. These standard impedances are typically It is disposed on the surface of a single side of a substrate and is called an impedance standard substrate.

However, due to system circuit miniaturization, SiP technology system level assembly and three-dimensional The key technology development of wafer silicon via (TSV) wafer stacking is in the ascendant. The I/O port of the signal-to-test signal transmission line is no longer distributed on the same plane as the traditional wafer process type, but distributed. On different planes of the system line; for example, in the actual measurement of the device under test such as the BGA package structure, since the device under test has two-sided contacts, the two of the vector network analyzers One of the probes must be calibrated on the single side of the standard substrate and then rotated 180 degrees to enable measurement of the device under test.

Obviously, the prior art cannot avoid the process of this rotation, and this rotation process not only requires a complicated mechanism, but also causes the original correction value to be distorted after the rotation, thereby affecting the accuracy of the measurement, and after the conversion, The trusted operating frequency is less than 10 GHz, and the measurement bandwidth cannot be effectively improved. This is also the biggest limitation of this prior art.

In view of the limitations of the prior art, the inventor of the present invention has proposed the patent No. I237120 of the present invention to overcome the problem. Referring to FIG. 2, one of the standard impedance substrates 14 disclosed in the present invention includes a copper core 15 and The two insulating layers 16 respectively cover the two sides of the copper core 15 respectively. The two insulating layers 16 respectively have two through holes 161 defining two contacts 162 for electrically connecting to the copper core 15 , thereby forming a Through circuit.

Therefore, the use of the standard impedance substrate 14 eliminates the need for additional rotation during calibration, and a relatively correct correction value can be obtained. However, this design is susceptible to electromagnetic wave interference due to high frequency signals, and the correction value is still distorted. Produced; in addition, the two insulating layers 16 do not completely cover the copper core 15 so that the exposed portion of the copper core 15 is also easily The external electrical signal is affected, reducing the overall correction accuracy.

Therefore, an object of the present invention is to provide a through-correction substrate having a high-frequency characteristic measurement, the through-correction substrate having contacts on both sides, so that when the measurement method is performed, the correction data on both sides can be obtained without rotating And it has the function of suppressing the high-frequency electromagnetic wave from the external electrical signal.

Therefore, the through-correction substrate of the high-frequency characteristic measurement of the present invention comprises a metal layer, an upper insulating dielectric layer disposed on a top surface of the metal layer, a lower insulating dielectric layer disposed on a bottom surface of the metal layer, and a high frequency Electromagnetic wave suppression unit.

Wherein, the upper insulating dielectric layer defines an upper contact region for a portion of the top surface of the metal layer to be exposed through the upper contact region; and the lower insulating dielectric layer is also provided with a lower contact region for the metal layer a portion of the bottom surface is exposed through the lower contact region, and the upper and lower insulating dielectric layers are interfitted to cover the periphery of the metal layer, and the upper and lower contact regions are formed through the metal layer. Electrically connected to form a double-sided straight-through circuit; the high-frequency electromagnetic wave suppression unit has two layers of suppression layers respectively disposed on the upper and lower insulating dielectric layers, and each of the suppression layers also has a notch for correspondingly communicating The upper and lower contact areas.

The utility model has the advantages that the two sides of the upper and lower contact areas can be squatted under the premise of not rotating the two probes of the vector network analyzer or rotating the straight through correction substrate itself to obtain two sides. In addition to the correction data, the design of the two suppression layers of the high-frequency electromagnetic wave suppression unit can also effectively isolate the interference of the high-frequency electromagnetic waves during the correction, and utilize the upper and lower The edge dielectric layer covers the periphery of the metal layer, and the external electrical signal is directly affected to the metal layer to improve the calibration accuracy.

The above and other technical contents, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments.

Referring to FIG. 3, a general vector network analyzer 20 is used. The vector network analyzer 20 has a high frequency signal generator 21 (RF Source) to provide a high frequency signal and is switched via a switch 22 (change -over switch), alternately connected to two separate measurement ports 23, 24. The two measuring electrodes 23, 24 respectively have a probe 25, 26 connected to a device under test (DUT) 27, whereby the high frequency signal is sent to the device under test 27.

The signal test module 28, 29 of the vector network analyzer 20 separates the high frequency signal sent to the device under test 27 from the signal reflected by the device under test 27, and processes the signals. And the measurement operation of the device under test 27 is completed.

Referring to Figures 4 and 5, a preferred embodiment of the through-correction substrate 3 of the high-frequency characteristic measurement of the present invention is applied to a calibration procedure before performing the above-described measurement operation to obtain correction data on the upper and lower sides, and thereby The element to be tested 27 having the contacts on the upper and lower sides is directly measured to remove errors outside the element to be tested 27.

The overall structure of the through-correction substrate 3 mainly includes a metal layer 31, an upper insulating dielectric layer 32 disposed on the top surface of the metal layer 31, and a lower insulating dielectric layer 33 disposed on the bottom surface of the metal layer 31, and a high Frequency electromagnetic wave suppression Unit 36.

The upper insulating dielectric layer 32 defines an upper contact region 34 for a portion of the top surface of the metal layer 31 to be exposed through the upper contact region 34. The lower insulating dielectric layer 33 is also provided with a lower contact region 35. A portion of the bottom surface of the metal layer 31 is exposed through the lower contact region 35, and the upper and lower insulating dielectric layers 32, 33 are fitted to each other to cover the periphery of the metal layer 31. The lower contact regions 34 and 35 are electrically connected via the metal layer 31 to form a double-sided through circuit A.

The double-sided straight-through circuit A disclosed in the embodiment has three contacts A1, A2, and A3 for electrically contacting the two ground terminals and one signal terminal, and of course, one ground terminal as shown in FIG. And the type of the signal end, so it should not be limited to the content disclosed in the embodiment.

In addition, the dielectric constants of the upper and lower insulating dielectric layers 32 and 33 are between 2 and 11. Generally, BT resin (Bismalemide Triazine Resin), Duroid material, or ceramic material may be used. BT resin was developed by Mitsubishi Gas Corporation of Japan, and Duroid material is a range of dielectric constant (r) material products developed by Rogers. The product type is from low dielectric constant RT/duroid 5870 (r=2.33) and 5880. (r = 2.2), to high dielectric constant RT / duroid 6006 (r = 6.15) and 6010 (r = 10.2), as for the metal layer 31 is generally made of copper material, or is a gold material Nickel is made and partially coated on the joints A1, A2, A3 to avoid oxidation of the gold material.

The high-frequency electromagnetic wave suppression unit 36 has two layers of suppression layers 361, 361' respectively disposed on the upper and lower insulating dielectric layers 32, 33, and each suppresses The layers 361, 361' also define a notch 362, 362' for correspondingly communicating the upper and lower contact regions 34, 35.

In order to achieve the purpose of suppressing high-frequency electromagnetic wave radiation (EMI), the suppression layer 361, 361' of the present embodiment may be provided with an electromagnetic energy gap structure (Electromagnetic Band Gap, EBG) as shown in FIG. ), and the EBG is not limited to one of the types shown in FIG. 6, and may be in the form shown in FIGS. 7 and 8, which is a periodic structure that is closer to the loop type.

In addition, there is also a pattern grounding shield (Pattern Ground Shield, hereinafter referred to as PGS) as shown in Figs. 9 and 10. Of course, there are other types of electromagnetic wave suppression circuits, which differ only in the degree of suppression from PGS and EBG. However, it will not be repeated here.

As can be seen from the ordinary knowledge in the technical field, the upper and lower contact areas 34, 35 and the matching gaps 362, 362' can be used as signal contacts or ground contacts for connection to FIG. Or the signal terminal or ground terminal of the probes 25, 26 as shown by the phantom line in FIG.

Therefore, when the calibration procedure needs to interconnect the input and output signals in different measurement plane directions, the through-correction substrate 3 of the embodiment can be used to perform three-dimensional direct correction of the measurement system. Specifically, FIG. 11 is adopted. A preferred embodiment of the high frequency characteristic measuring method 4 of the present invention is shown as follows:

The high-frequency characteristic measuring method 4 includes a preparation step 41, a calibration step 42, and a measurement step 43, wherein the preparation step 41 is to provide the through-correction substrate 3 shown in the foregoing FIGS. 4 and 5; In the correcting step 42, the two probes 25 and 26 of the vector network analyzer 20 shown in FIG. 2 are respectively The upper and lower contact regions 34, 35 (shown in FIG. 5) of the through-correction substrate 3 are slid down to obtain the correction data on both sides, and the correction of the vector network analyzer 20 is completed. Then, the measurement step 43 is performed, and the vector network analyzer 20 that completes the calibration operation is electrically connected to the device under test 27 having the upper and lower sides of the contact shown in FIG. 2 to perform the component 27 to be tested. Measurement work.

With the above design, applying the through correction substrate 3 of the present embodiment produces the following advantages:

(1) Improve calibration accuracy and measurement bandwidth:

After the vector network analyzer 20 obtains the correction data on both sides by using the through-correction substrate 3 of the embodiment, the device under test 27 having the upper and lower contacts can be directly measured, and the complicated mechanism is not required. In order to rotate the probe, the contact signal between the probes 25 and 26 and the vector network analyzer 20 is not closely contacted, and the relatively correct correction data can be obtained; Measuring axis conversion can effectively improve calibration and measurement bandwidth.

(2) Isolation of interference between high frequency electromagnetic waves and external electrical signals:

By designing the two suppression layers 361, 361' of the high-frequency electromagnetic wave suppression unit 36, the interference of the high-frequency electromagnetic waves can be effectively isolated during the correction; in addition, the metal is also utilized by the upper and lower insulating dielectric layers 32, 33. The periphery of the layer 31 is covered and sandwiched, and the external electrical signal directly affects the metal layer 31, thereby improving the quality of the signal transmission, obtaining good two-sided correction data, and improving the correction accuracy.

In summary, the high-frequency characteristic measurement of the through-correction substrate 3 of the present invention, The upper and lower insulating dielectric layers 32, 33 are directly coated on the top and bottom surfaces of the metal layer 31, and the upper and lower contact regions 34, 35 are opened for the two sides to squat, so when the amount is performed When the method 4 is tested, the vector network analyzer 20 does not need to rotate the probe to perform actual measurement after the correction, so the correction accuracy and the measurement bandwidth can be improved; The high-frequency electromagnetic wave suppression unit 36 is designed to isolate the interference of high-frequency electromagnetic waves, and the peripheral edges of the metal layer 31 are covered by the upper and lower insulating dielectric layers 32 and 33 to avoid direct influence of external electrical signals, so The object of the invention can be achieved.

The above is only the preferred embodiment of the present invention, and the scope of the invention is not limited thereto, that is, the simple equivalent changes and modifications made by the scope of the invention and the description of the invention are All remain within the scope of the invention patent.

20‧‧‧Vector Network Analyzer

21‧‧‧High frequency signal generator

22‧‧‧Toggle switch

23, 24‧‧‧Measurement

25, 26‧‧ ‧ probe

27‧‧‧Device under test

28, 29‧‧‧ Signal Test Module

3‧‧‧Through correction substrate for high frequency characteristic measurement

31‧‧‧metal layer

32‧‧‧Upper dielectric layer

33‧‧‧Under dielectric layer

34‧‧‧Upper contact area

35‧‧‧Under contact area

36‧‧‧High frequency electromagnetic wave suppression unit

361, 361’‧‧‧ suppression layer

362, 362’ ‧ ‧ gap

4‧‧‧High frequency characteristic measurement method

41‧‧‧Preparation steps

42‧‧‧ Calibration procedure

43‧‧‧Measurement steps

A‧‧‧Double-side straight-through circuit

A1, A2, A3‧‧‧ joints

1 is a schematic diagram of a standard impedance circuit, illustrating two probes of a vector network analyzer, a through circuit contacting a standard impedance substrate; and FIG. 2 is a side cross-sectional view showing one of the disclosed inventions in Japanese Patent Publication No. I237120 Standard impedance substrate; FIG. 3 is a system block diagram illustrating the manner in which the vector network analyzer measures the component to be tested; FIG. 4 is a perspective view illustrating a preferred embodiment of the through-correction substrate of the high-frequency characteristic measurement of the present invention; Figure 5 is a side elevational cross-sectional view of the preferred embodiment shown in Figure 4; Figures 6-8 are a top view illustrating the suppression layer of the preferred embodiment. The EBG structure of the surface is arranged; Figures 9 and 10 are a top view illustrating the PGS structure of the surface of the suppression layer of the preferred embodiment; and Figure 11 is a step flow chart illustrating the use of the aforementioned straight-through correction substrate A preferred embodiment of the high frequency characteristic measurement method performed.

25, 26‧‧ ‧ probe

3‧‧‧Through correction substrate for high frequency characteristic measurement

31‧‧‧metal layer

32‧‧‧Upper dielectric layer

33‧‧‧Under dielectric layer

34‧‧‧Upper contact area

35‧‧‧Under contact area

36‧‧‧High frequency electromagnetic wave suppression unit

361, 361’‧‧‧ suppression layer

362, 362’ ‧ ‧ gap

Claims (6)

A through-correction substrate for high-frequency characteristic measurement, comprising: a metal layer; an upper insulating dielectric layer disposed on a top surface of the metal layer, the upper insulating dielectric layer having an upper contact region for providing a top surface of the metal layer a portion of the region is exposed through the upper contact region; a lower insulating dielectric layer is disposed on the bottom surface of the metal layer, and the lower insulating dielectric layer is provided with a lower contact region for a portion of the bottom surface of the metal layer to pass through the lower contact region Exposed to the outside, and the upper and lower insulating dielectric layers are matched to each other to cover the periphery of the metal layer, and the upper and lower contact regions are electrically connected via the metal layer to form a double-sided straight-through circuit; And a high-frequency electromagnetic wave suppression unit having two layers of suppression layers respectively disposed on the upper and lower insulating dielectric layers, and each of the suppression layers also has a notch for correspondingly communicating the upper and lower contact regions. The through-correction substrate of the high-frequency characteristic measurement according to the first aspect of the patent application, wherein the surface of the suppression layer is provided with a pattern-type ground shielding structure. A through-correction substrate according to the high-frequency characteristic measurement described in claim 1 wherein the surface of the suppression layer is provided with an electromagnetic energy gap structure. A through-correction substrate according to the high-frequency characteristic measurement described in claim 1 wherein the metal layer is made of a copper material or is made of a gold material and is coated with nickel at the joint portion. a through-correction substrate according to the high-frequency characteristic measurement described in claim 1 wherein the dielectric constant of the upper and lower insulating dielectric layers is Between 2 and 11. The through-correction substrate according to the high-frequency characteristic measurement described in claim 5, wherein the upper and lower insulating dielectric layers are made of Bismalemide Triazine resin, Duroid material, or ceramic material.