TW200406950A - Method to produce electrical wire-structures usable in high frequency technology - Google Patents

Abstract

A method to produce on a wire-structure-carrier with layer-distances much smaller than 180 um, for example, 30 um, electrical wire-structures usable in high frequency technology under the use of micro-strips-conductors is given. According to this method, a combination of a laser-structurization method with an etching method in connection with a resist is performed, said resist has some properties at least with respect to the laser in the laser-structurization method, the etching in the etching method and its maximal thin applicability on the wire-structure-carrier, said properties correspond at least to the ones of chemical tin or an amorphous resist.

Description

200406950 (1) Description of the invention: [Technical field to which the invention belongs] The present invention relates to a method for manufacturing a line structure that can be used on a line structure carrier in high-frequency technology. [Prior art] In the current circuit board technology, a suitably large structure for a resonator, a band-pass filter, a band stopper, and a spiral inductor is required. For example, when using a relatively thin insulation layer of the order of 50 um, the current large tolerances of conductive rails currently in a series of products are generally not allowed to be used for micro-strip conductors. In each case, the use of microstrip conductors is greatly limited due to the higher tolerance of the conductive tracks. For example, microstrip conductors are currently not suitable for use in high-frequency technology. When ceramics are used, a long running time is required in the manufacturing process as compared with a circuit board used as a carrier of a circuit structure. In addition, the benefits when using ceramics compared to circuit boards are much lower. Moreover, ceramics are not suitable for use as an optical carrier. In order to avoid large structures such as resonators, band-pass filters, band cut-offs, and spiral inductors, all components have been used on the surface of circuit boards so far due to space reasons. These components increase costs. Setting the components on the circuit board also increases the cost. Other disadvantages are: the surface of the circuit board needs to prepare the required setting surface for each component. In the so-called FR4 circuit board, the micro-strip conductor is used on the existing area that is large enough in the high-frequency (HF) part, but this is particularly limited to the distance between these layers to the high-frequency structure (for example, greater than 100 um) The position of each face of) ° is acceptable in the conductive track when such a layer distance. 200406950 [Summary of the invention] The object of the present invention is to provide a method for manufacturing a line structure that can be used on a line structure carrier in high-frequency technology. When using a micro-strip conductor, the distance between the layers is much smaller than 00um. . The above object in the present invention is achieved by the method described in item 1 of the scope of patent application. The combination of laser structuring method and etching method is performed with a photoresist having a high adhesive strength. The photoresist has various characteristics at least in the laser structuring method for the laser or in the etching method for the etching and its maximum thin layer applicability on the line structure carrier, and these characteristics correspond to At least one of chemical tin- or amorphous photoresist characteristics. The chemical tin can be coated to have a thickness of about 1 um. The thickness of the amorphous photoresist can be much smaller than 20 um. The thinner the photoresist, the more suitable it is for this method. The current photoresist has a much larger thickness than 20 um. The much thinner photoresist allows the laser to operate in a much more accurate manner. Each structure can therefore be in the range of 20 μm-or 10 μm-or less in an optimized process. These subtle structures can form the circuit structure used in high-frequency technology, and they can also replace the required traditional components with disadvantages. In detail, the above-mentioned circuit structure must be formed so as to form capacitors, coils, and resistors effective for high-frequency technology in the minimum space required. This laser structuring method therefore allows a structuring for lithography in a simpler way (but at a higher rate). In addition, the combination of the laser structuring method and the uranium engraving method has the advantage that the all-plane area can be removed simultaneously with other areas. This saves time, but it is usually needed, so the circuit structure that can be used in high 200406950 frequency technology will not be adversely affected by the electric field that may exist in the all-plane area. Overall, the conductive rails structured by this method can be made in the form of micro-strip conductors on the inner layer or the outer layer of the circuit board with a small tolerance, which has approximately any arbitrary Features. The width of the conductive track can be almost arbitrarily defined. The tolerance is currently less than +/- 5 um. The previous typical tolerance was in the range of +/- 25 um. Advantageous forms of the invention are described in the subordinates of the scope of the patent application. FR 4-carrier material was then used as the circuit structure carrier. This material is known and low cost. The advantage of chemical tin or amorphous photoresist is that when combined with the laser structuring method and the uranium engraving method, various circuit structures used in high frequency technology can be made. [Embodiment] The present invention will be described in detail below with reference to the drawings. The partially-constructed conductor diagram (PHDI: Partial High Density Interconnection) shown in Figure 1 shows a line structure carrier 1 (substrate, for example, a FR4-circuit board) with a suitable surface This is pretreated in an initial coating phase so that a thin copper layer can be applied chemically. Another coating is applied during the subsequent electrolytic coating process. In this embodiment, the total thickness of these layers can reach 20 μm. A thin photoresist layer is then applied, which is made of chemical tin and is approximately 1 um thick. This coating phase is immediately followed by a structured phase. This structuring is carried out by laser according to Fig. 1. Laser 200406950 was used in this structured phase to remove the chemical tin layer on these locations (the copper layer below the chemical tin layer should be stripped later) by milling. As described above, the bare copper layer is etched and removed after the structured phase. The remaining chemical tin layer is then stripped. The circuit structure of the present invention is shown in the upper left area of FIG. 2, and the conventional circuit structure is shown in the central area. When one of the preset circuit structures of the present invention and a conventional circuit structure have been made, Fig. 3 shows the ratio in size. Figures 4 to 7 show the steps in forming a coil made of a microstrip conductor in the present invention. Figure 4 shows a copper area with a side length of 1 mm. The copper area is structured with a laser in the respective manufacturing steps. A spiral-shaped coil can be identified from FIG. 5. Figure 6 removes the angular areas of each interference. The coil in Figure 7 has been made. Figures 8 to 10 show various existing applications, mainly coils, in side view. The form and size of each figure can be arbitrarily selected. In this embodiment, the most compact form is selected separately. Figure 11 shows a possible application of a component underneath a component in a circuit board. In the form shown, the circuit board does not require a setting surface. These coils can also be installed in any other position during layout. Fig. 12 shows a case in which it is used as a capacitor under a connection pad (Pad). By using a suitable isolation layer and a small layer thickness (e.g., as small as 25 um), a capacitor with a size of up to 20 pF can be made in the smallest space. Another advantage of these capacitors is that they are almost non-inductive. Figure 13 shows the application of a high frequency (HF) capacitor. Figure 14 is the application of 200406950 high frequency (HF) coil. Figure 15 shows the application of high-frequency resistance, and Figure 16 shows the application of moisture sensor. [Brief Description of the Drawings] Figure 1 A schematic illustration of the method flow of the present invention. FIG. 2 A part of a cross section of a larger circuit board structure made according to the method of FIG. 1, which has a circuit structure usable in high-frequency technology and a circuit usable in non-high-frequency technology structure. FIG. 3 is a comparison diagram of the size of the circuit structure of the present invention and the corresponding conventional technology. Figures 4 to 7 are steps when a coil is made in the present invention. Figures 8 to 10 Side views of three completed applications in a circuit board made according to the present invention. Figures 11 and 12 show other applications of the present invention. Figures 13 to 16 Various applications in the present invention are exemplified by capacitors, coils, resistors and moisture sensors. Symbol description of main components: Isolation layer Isolation layer

Ll, L2, L3 lines

Claims (1)

200406950 Scope of patent application: 1 · A method of manufacturing a line structure that can be used on a line structure carrier in high-frequency technology, which is characterized by using a type of laser structured in the case of using a photoresist A combination of a method and an etching method, the photoresist, at least for the laser in the laser structuring method or in the etching method for the etching and its maximum thin layer applicability on the line structure carrier Both have various characteristics, which correspond to at least one of chemical tin- or amorphous photoresist characteristics. 2. The manufacturing method according to item 1 of the patent application scope, wherein a FR4-carrier material is used as a circuit structure carrier. 3. The manufacturing method according to item 1 or 2 of the patent application scope, wherein chemical tin or amorphous photoresist is used as the photoresist. 4. The manufacturing method according to item 1, 2 or 3 of the scope of patent application, wherein at least one of the peripheral arrays composed of circuit structures usable in high-frequency technology is used to remove at least a large area of circuit structures still remaining. -10-