JP5155269B2 - High-speed electrical track - Google Patents

Description

  The present invention relates to a high-speed electric line, and more specifically, it is possible to provide a flexible high-speed electric line having flexibility used when three-dimensionally connecting different parts or different parts on the same surface. The present invention relates to a rigid high-speed electric line.

  With the increase in the signal speed of electric signals and the narrowing of the pitch between electrodes provided in small parts, a light and thin substrate having a low loss and a fine pitch electric line is desired.

In order to suppress a loss that occurs during propagation of an electric signal, there is a multi-layer substrate system in which a fluororesin such as PTFE is used as a substrate material and the glass cloth is infiltrated. (For example, see Patent Document 1)
Furthermore, in order to electrically connect components provided at different heights and positions, a flexible substrate having flexibility as a single layer substrate may be used.

  FIG. 3 shows a grounded coplanar line formed on a substrate 3-1 in which a resin is infiltrated into a conventional glass cloth. 4 shows a CC cross section of FIG. A differential gland composed of a ground-positive signal-negative signal-ground electric line 3-2, 3-3, 3-4 on one surface of a resin containing warp yarns 3-7 and weft yarns 3-8 inside. A dead coplanar electrode (electrode Diff.-GCPW) is formed, and a ground electrode 3-6 is uniformly formed on the other surface facing each other.

US Pat. No. 6,783,481

  However, of the two electric lines 3-2 and 3-3 constituting the differential transmission path, a weft of glass fiber is located over the length of the electric path in the lower part of one of the electric lines 3-3. Since the electric line 3-3 is more affected by the glass fiber, a signal propagation speed difference is generated between the electric line 3-2 and the electric line 3-3. This signal propagation speed difference causes a skew difference in the signal propagating through the electric line, and there is a problem of causing a cross-point shift and jitter in the differential signal waveform after transmission.

  In addition, PTFE and liquid crystal polymer, which are characterized by low loss, are softened when exposed to temperatures of 300 ° C. or higher as their material characteristics. When connecting with, there was a problem in its reliability.

  There are cases where PTFE and liquid crystal polymer are infiltrated into glass cloth for the purpose of low loss and improvement in solder temperature resistance, but the electrical signal pitch interval has become narrower as the substrate becomes thinner, especially as a differential electrical line. When a glass cloth is positioned at the lower side of either the positive electric line or the negative electric line in parallel or at an angle close to the line in use, the speed change of the electric signal transmitted through each line results. Therefore, there is a concern about an increase in jitter and the like, and a method capable of solving the above two points simultaneously has been desired.

  The present invention has been made in view of such problems, and the object of the present invention is to improve the soldering heat resistance at the soldering point, especially when the electric line is used as a differential electric line. An object of the present invention is to provide a high-speed electric line that improves the signal quality.

In order to solve the above-mentioned problems, the invention according to claim 1 is a high-speed electric line, and is provided with flexibility in which a resin is soaked in a glass fiber cloth in which a plurality of glass fibers are alternately knitted. A film having different cross density of glass fibers in both the region A in the range of L (mm) from the edge of the film and the region B other than the region A, and the first surface of the film And an electric line formed on the second surface facing the first surface so as not to be parallel to the glass fiber, and the cross density of the glass fibers in the region A Is higher than the cross density of the glass fibers in the region B.

Metal The invention according to claim 2, in high-speed electrical line according to claim 1, wherein the electrical line is formed in the region A of the second surface, using a set of (ground, signal, ground) A single-ended grounded coplanar electrode (electrode Single-Ended-GCPW) having a film arranged in order and having a ground electrode on the first surface, and a single-ended coplanar electrode having no ground electrode on the first surface (Electrode Single-Ended-CPW),
A differential grounded coplanar electrode (electrode Diff.-GCPW) having a ground electrode on the first surface is arranged in order, and metal films used in a set of (ground, positive signal, negative signal, ground), the first No. 1 differential coplanar electrode (electrode Diff.-CPW) without a ground electrode, or the electrode Single-Ended-GCPW, the electrode Single-Ended-CPW, the electrode Diff. -GCPW, electrode Diff. -At least two or more electrodes of arbitrary combinations of CPW are provided.

Invention according to claim 3, in high-speed electrical line according to claim 1, wherein the conductor includes a first surface ground electrode formed in a region B of the electric line, the second A single-ended microstrip line (line MSL) formed only in an electric line formed on the surface area B, a ground on the bottom of the film, and a metal film arranged in the order of (ground, signal, ground) on the surface・ A differential grounded coplanar line with metal films used in order of a grounded coplanar line (line Single-Ended-GCPW), (ground, positive signal, negative signal, ground) and a ground electrode on the bottom. (Line Diff.-GCPW), or the line MSL, line Single-Ended-GCP , Line Diff. -It has at least one line of arbitrary combinations of GCPW.

According to a fourth aspect of the present invention, in the high-speed electric line according to the second aspect, the conductor includes a ground electrode formed in a region B of the first surface, and the electric line includes the second electric line. A single-ended microstrip line (line MSL) formed only in an electric line formed on the surface area B, a ground on the bottom of the film, and a metal film arranged in the order of (ground, signal, ground) on the surface・ A differential grounded coplanar line with metal films used in order of a grounded coplanar line (line Single-Ended-GCPW), (ground, positive signal, negative signal, ground) and a ground electrode on the bottom. (Line Diff.-GCPW), or the line MSL, line Single-Ended-GCP , Line Diff. -It has at least one line of arbitrary combinations of GCPW.

The invention according to claim 5 is the high-speed electric line according to claim 4 , wherein when the electrode Single-Ended-GCPW or the electrode Single-Ended-CPW is electrically connected, the line MSL or the line A line Single-Ended-GCPW is used.

According to a sixth aspect of the present invention, in the high-speed electric line according to the fourth aspect , the electrode Diff. -GCPW or the electrode Diff. -When the CPW is electrically connected, the line Diff. -GCPW is used.

The invention described in claim 7 is the high-speed electric line according to claim 5 or 6 , wherein the resin soaked in the glass fiber is an epoxy resin, a polyimide resin, a fluorine resin, or a liquid crystal polymer resin. Features.

In claim 8, in high-speed electrical line according to claim 7, characterized in that it comprises a thick rigid board than the film on the first surface.

  The present invention selectively improves the solder heat resistance at the soldering location by selectively increasing the density of the glass fiber at the end of the substrate where soldering is assumed. By arranging so as not to be parallel to the electrical line, it is possible to prevent the glass fiber from being positioned along the electrical line directly below the electrical line, especially when the electrical line is used as a differential electrical line. Improve signal quality.

  The present invention has an effect of improving solder heat resistance at a soldering location, and further improving signal quality after transmission, particularly when an electric line is used as a differential electric line.

1 is an overall view of an electric line according to a first embodiment of the present invention. It is a general view of the electrical track which concerns on the 2nd Embodiment of this invention. It is a general view which shows the grounded coplanar track | line formed on the board | substrate 3-1 which made resin permeate the conventional glass cloth. It is CC sectional drawing of FIG.

  Hereinafter, embodiments of the present invention will be described in detail. In all the embodiments, the substrate material soaked in the glass fiber can be composed of any of an epoxy resin, a polyimide resin, a fluorine resin, or a liquid crystal polymer resin, and the structure of the electric line according to the consumption line impedance. It goes without saying that parameters such as the line width and the pitch interval with the ground are automatically determined from the substrate thickness and conductor thickness.

(First embodiment)
FIG. 1 shows an overall view of an electric line according to the first embodiment of the present invention. Here, a single-ended transmission line 1-7 and a single-ended coplanar transmission line 1-8 are formed on a single substrate 1-1 in which a substrate material is soaked in a glass cloth 1-2. A ground electrode is uniformly formed on the surface of the substrate 1-1 that faces the surface constituting the single-ended transmission line. When the ground electrode is uniformly provided on the back surface of the region of the substrate 1-1 where the single-ended coplanar transmission line 1-8 is formed, the single-ended coplanar transmission line 1-8 is a single-ended grounded coplanar line. Needless to say.

  Single-ended coplanar electrodes 1-5 and 1-6 are provided at the end of each transmission line, assuming connection with other boards and components. Moreover, in the area | region 1-3 in which each electrode was formed, the density of the glass fiber which comprises a glass cloth is selectively high compared with the area | region 1-4 in which the transmission line was formed. Thereby, when connecting with other components or a board | substrate by solder, press, etc., temperature tolerance and mechanical strength are improved. The region 1-3 can be a region of about 0.5 mm to 2 mm from the end surface of the substrate.

  In the present invention, by arranging the glass fiber and the transmission line so as not to be parallel to each other, it is avoided that the glass fiber is located directly below the transmission line along the longitudinal direction of the transmission line. In the region 1-4 where the transmission line is formed, the low density of the glass fibers not only improves the flexibility as a flexible substrate, but also intersects the glass fibers located directly under the transmission line via the substrate material. Since the number decreases, impedance fluctuation is reduced and transmission characteristics are improved.

(Second Embodiment)
FIG. 2 shows an overall view of an electric line according to the second embodiment of the present invention. Here, three types of differential lines are formed on one substrate 2-1 in which a substrate material is soaked in a glass cloth 2-2. In order from the top in the drawing, the first transmission path 2-4 composed of (ground-positive signal-ground-negative signal-ground) lines, (ground-positive signal-ground-ground-negative signal-ground) A second transmission path 2-5 composed of a line, and a third transmission path 2-6 composed of a line of (ground-positive signal-negative signal-ground).

  As in the first embodiment, the glass fiber and the transmission line are arranged so as not to be parallel to each other, thereby avoiding the glass fiber being located directly below the longitudinal direction of the transmission line. Thereby, generation of skew between the positive signal and the negative signal is suppressed, and good differential electric signal transmission is possible.

  Further, in the region 2-3 where the respective electrodes are formed, the density of the glass fibers constituting the glass cloth is selectively higher than that in the region 2-4 where the transmission path is formed. Thereby, when connecting with other components or a board | substrate by solder, press, etc., temperature tolerance and mechanical strength are improved. In the region 2-4 in which the transmission line is formed, the density of the glass fiber is low, so that not only the flexibility as the flexible substrate is improved, but also the intersection of the glass fibers located directly below the transmission line via the substrate material. Since the number decreases, impedance fluctuation is reduced and transmission characteristics are improved. The region 2-3 can be a region of about 0.5 mm to 2 mm from the end surface of the substrate.

  The first and second embodiments can be mounted on a substrate thicker than the substrates 1-1 and 2-2 in order to obtain further strength.

1-1, 2-1, 3-1 Substrate 1-2, 2-2 Glass cloth 1-3, 2-3 Area where electrodes are formed 1-4, 2-4 Area where transmission lines are formed 1- 5, 1-6 Single-ended coplanar electrode 1-7 Single-ended transmission line 1-8 Single-ended coplanar transmission line 2-4 First transmission line 2-5 Second transmission line 2-6 Third transmission line 3-2, 3-3, 3-4 Electrical line 3-5 Electrode Diff. -GCPW
3-6 Ground electrode 3-7 Warp of glass cloth 3-8 Weft of glass cloth

Claims (8)

A flexible film in which a glass fiber cloth in which a plurality of glass fibers are alternately knitted is impregnated with a resin, the region A being in the range of L (mm) from the edge of the film, and the region A film in which the cross density of glass fibers is different in both regions B other than A,
A conductor uniformly formed on the first surface of the film;
An electrical line formed on the second surface opposite to the first surface so as not to be parallel to the glass fiber, and the cross density of the glass fibers in the region A is the crossing of the glass fibers in the region B A high-speed electrical line characterized by higher density . The electrical line is formed in the region A of the second surface,
A single-ended grounded coplanar electrode (electrode Single-Ended-GCPW) having a metal electrode used in a set of (ground, signal, ground) in order and having a ground electrode on the first surface;
A single-ended coplanar electrode (electrode Single-Ended-CPW) without a ground electrode on the first surface;
(Ground, positive signal, negative signal, ground) are arranged in order, and a differential grounded coplanar electrode (electrode Diff.-GCPW) having a ground electrode on the first surface,
A differential coplanar electrode (electrode Diff.-CPW) without a ground electrode on the first surface, or
The electrode Single-Ended-GCPW, the electrode Single-Ended-CPW, the electrode Diff. -GCPW, electrode Diff. The high-speed electric line according to claim 1 , comprising at least two or more electrodes of any combination of CPW. The conductor includes a ground electrode formed in the region B of the first surface,
The electrical line is formed in the region B of the second surface,
Microstrip line (line MSL) only for electric lines,
A single-ended grounded coplanar line (line Single-Ended-GCPW) having a ground on the bottom surface of the film and a metal film arranged in the order of (ground, signal, ground) on the surface,
(Ground, positive signal, negative signal, ground) Metal films used in pairs are sequentially arranged, and a differential grounded coplanar line (line Diff.-GCPW) having a ground electrode on the bottom surface, or
The line MSL, the line Single-Ended-GCPW, the line Diff. Fast electric line according to claim 1, characterized in that any combination of lines -GCPW comprising at least one or more. The conductor includes a ground electrode formed in the region B of the first surface,
The electrical line is formed in the region B of the second surface,
Microstrip line (line MSL) only for electric lines,
A single-ended grounded coplanar line (line Single-Ended-GCPW) having a ground on the bottom surface of the film and a metal film arranged in the order of (ground, signal, ground) on the surface,
(Ground, positive signal, negative signal, ground) Metal films used in pairs are sequentially arranged, and a differential grounded coplanar line (line Diff.-GCPW) having a ground electrode on the bottom surface, or
The line MSL, the line Single-Ended-GCPW, the line Diff. The high-speed electric line according to claim 2 , comprising at least one line of any combination of -GCPW. The electrode Single-Ended-GCPW, or when electrically connecting the electrodes Single-Ended-CPW, in claim 4, wherein the line MSL, or the line Single-Ended-GCPW is used The described high-speed electrical line. The electrode Diff. -GCPW or the electrode Diff. -When the CPW is electrically connected, the line Diff. 5. The high-speed electric line according to claim 4 , wherein GCPW is used. The glass fibers stain crowded so the resin is an epoxy resin, polyimide resin, fluorine-based resin or high speed electrical line according to claim 5 or 6, characterized in that a liquid crystal polymer resin. 8. The high-speed electric line according to claim 7 , further comprising a rigid substrate thicker than the film on the first surface side.

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