CN111256578A - Method for detecting depth of back drilling plate - Google Patents
Method for detecting depth of back drilling plate Download PDFInfo
- Publication number
- CN111256578A CN111256578A CN202010069872.9A CN202010069872A CN111256578A CN 111256578 A CN111256578 A CN 111256578A CN 202010069872 A CN202010069872 A CN 202010069872A CN 111256578 A CN111256578 A CN 111256578A
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- hole
- drilling
- back drilling
- depth
- drill
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/26—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring depth
Abstract
The invention provides a method for detecting the depth of a back drilling plate, which comprises the following steps: s1, confirming the drilling depth: the back drilling of the early drilling needs to be carried out by slicing to confirm the drilling depth; s2, 2 back drilling modules are designed and tested on the edge/technical edge of the PNL board, and the drilling depth condition of the back drilling hole can be judged by the testing modules through the on-off performance of electric testing. The invention adopts the PCB waste area to design the back drilling module, and verifies the reliability of the back drilling depth by combining the back drilling with the conductivity of the circuit, thereby facilitating the operation flow and monitoring the back drilling quality of all production boards. The detection method of the invention greatly reduces the detection time and the detection accuracy and is beneficial to quality monitoring.
Description
Technical Field
The invention relates to the field of quality monitoring and efficiency improvement in production of high-frequency and high-speed PCB (printed circuit board), in particular to a method for detecting the depth of a back drilling board.
Background
At present, in the process of manufacturing a Printed Circuit Board (PCB), copper-plated through holes can be regarded as lines, and the ends of some copper-plated through holes are not connected, which results in the retrace of signals, and resonance is also reduced, which may cause reflection, scattering or delay of signal transmission, and finally cause the problem of signal distortion. The backdrill process (backdrill) removes the via copper of the via segment that does not serve any connection or transmission function, so as to avoid the problem that the remaining via copper of the via segment causes the signal distortion. In the quality control of the back drilling process, the back drilling depth control is a key factor influencing the signal integrity, and therefore, the back drilling depth must be effectively controlled in the actual production of the PCB. The hole drilled using the backdrilling process is called a backdrill hole (Back drill hole), and the step of making the backdrill hole is: drilling a through hole on the PCB, then plating copper on the inner wall of the through hole to form a copper-plated through hole, and finally drilling an inverted granary-shaped hole with a cone below and a cylinder above on the soldering tin surface of the PCB, wherein the diameter of the hole is larger than that of the copper-plated through hole, so that hole copper on the inner wall of the copper-plated through hole can be removed.
In the back drilling process, the prior art needs to specially slice to confirm the depth of a blind hole in the early production process, cannot confirm every PNL production plate by 100 percent, and has long slicing and grinding time and low efficiency. Therefore, how to improve the inspection efficiency and effectively ensure the quality of each PNL production board is the key of the problem.
Disclosure of Invention
In view of the above, the present invention provides a method for detecting the depth of a back-drilled board, which adopts a PCB waste area to design a back-drilled module, and verifies the reliability of the back-drilled hole depth by combining the conductivity of the back-drilled hole and the circuit, so as to facilitate the operation process and monitor the back-drilled quality of all production boards. The detection method of the invention greatly reduces the detection time and the detection accuracy and is beneficial to quality monitoring.
The technical scheme of the invention is as follows:
a method for detecting the depth of a back drilling plate is characterized by comprising the following steps:
s1, confirming the drilling depth: the back drilling of the early drilling needs to be carried out by slicing to confirm the drilling depth; so as to monitor the actual depth of the back drilling of the drilled hole, and the production plate can not be confirmed by 100 percent of slicing due to the complex grinding process and long grinding time of the slicing grinding process;
s2, 2 back drilling modules are designed and tested on the edge/technical edge of the PNL board, and the drilling depth condition of the back drilling hole can be judged by the testing modules through the on-off performance of electric testing.
Further, in step S2, a blind VIA hole diameter in the board is designed in each test module, the blind VIA hole diameter is conducted with the designed circuit and each layer of VIA aperture, the blind VIA hole distance is 1.1-1.8mm, and the circuit line width is designed to be 5-9 mil.
Further, in the step S2, the blind bore diameter is 0.2mm larger than a bore diameter.
Further, in step S2, the size of the via hole is designed according to the size of the back drill hole-drill hole diameter.
Further, in the step S2, a ring is designed at the outer layer via hole of each test module, the ring of the back drilling hole is 2mil larger than the single side of the back drilling hole, and the back drilling hole is 4mil larger than the single side of the back drilling hole.
Further, in step S2, each test module text layer is designed with a corresponding blind hole test character, the layer to be drilled by the back drill and the layer corresponding to the VIA aperture are required to be conducted, the character is required to be matched with the actual line layout, and the design depth of the drilling tape data is matched with the indication of the actual back drill layer number.
In the present invention, the detection method can be summarized as the following steps: adding a test module in a vacant area or a process edge of a PCB; after back drilling, the corresponding layer is disconnected with the VIA hole, the electrical test is not conducted, and the situation that the corresponding layer is drilled through is obtained; designing inner layer circuits, wherein each VIA hole corresponds to a corresponding layer; the outer layer characters are remarked with the corresponding inner layer layers communicated with the VIA holes.
Furthermore, the test module further comprises at least one back drilling detection hole which is arranged on the board edge of the printed circuit board and used for detecting the alignment of the back drilling, wherein the aperture of each back drilling detection hole is smaller than the diameter of the back drilling hole, and the aperture is determined by the diameter of the back drilling hole and the preset different back drilling offset.
Furthermore, the test module further comprises an identification module, and the identification module is used for identifying the preset back drilling offset corresponding to each back drilling detection hole.
Furthermore, the test module can sequentially penetrate through the back drilling hole to observe the base materials around the back drilling detection hole corresponding to the back drilling hole according to the sequence of the preset back drilling offset from small to large, and when the base materials around the back drilling detection hole are observed through the back drilling hole, the offset of the back drilling hole is the preset back drilling offset corresponding to the back drilling detection hole.
The test module can also be used for sequentially observing the base materials around the back drilling detection hole according to the sequence of the offset from small to large and taking the preset back drilling offset corresponding to the back drilling detection hole capable of observing the base materials as the offset of the back drilling hole, so that the offset of the back drilling hole can be quickly and accurately determined, and the problems of large workload, time consumption, difficulty in judgment and the like caused by the alignment of the back drilling detection of the section detection can be effectively assisted.
The invention has the beneficial effects that:
1. the material and production cost are unchanged, the grinding and slicing processes can be reduced without inputting new equipment, and the production efficiency is improved;
2. all back drilling boards can be provided with a test module, the depth condition of the back drilling hole is verified through an electrical measurement process, the back drilling quality can be comprehensively monitored by effectively aligning and detecting without adding a new process.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the detailed description and specific examples, while indicating the scope of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
Example 1
A method for detecting the depth of a back drilling plate is characterized by comprising the following steps:
s1, confirming the drilling depth: the back drilling of the early drilling needs to be carried out by slicing to confirm the drilling depth; so as to monitor the actual depth of the back drilling of the drilled hole, and the production plate can not be confirmed by 100 percent of slicing due to the complex grinding process and long grinding time of the slicing grinding process;
s2, 2 back drilling modules are designed and tested on the edge/technical edge of the PNL board, and the drilling depth condition of the back drilling hole can be judged by the testing modules through the on-off performance of electric testing.
Further, in step S2, a blind VIA hole diameter in the board is designed in each test module, the blind VIA hole diameter is communicated with the designed circuit and each layer of VIA aperture, the blind VIA hole distance is 1.5mm, and the circuit line width is designed to be 7 mil.
Further, in the step S2, the blind bore diameter is 0.2mm larger than a bore diameter.
Further, in step S2, the size of the via hole is designed according to the size of the back drill hole-drill hole diameter.
Further, in step S2, a ring is designed at the outer layer via hole of each test module, the ring of the back drilling hole is 2mil larger than the single side of the back drilling hole, and the back drilling hole is 4mil larger than the single side of the back drilling hole.
Further, in step S2, each test module text layer is designed with a corresponding blind hole test character, the layer to be drilled by the back drill and the layer corresponding to the VIA aperture are required to be conducted, the character is required to be matched with the actual line layout, and the design depth of the drilling tape data is matched with the indication of the actual back drill layer number.
In the present invention, the detection method can be summarized as the following steps: adding a test module in a vacant area or a process edge of a PCB; after back drilling, the corresponding layer is disconnected with the VIA hole, the electrical test is not conducted, and the situation that the corresponding layer is drilled through is obtained; designing inner layer circuits, wherein each VIA hole corresponds to a corresponding layer; the outer layer characters are remarked with the corresponding inner layer layers communicated with the VIA holes.
Furthermore, the test module further comprises at least one back drilling detection hole which is arranged on the board edge of the printed circuit board and used for detecting the alignment of the back drilling, wherein the aperture of each back drilling detection hole is smaller than the diameter of the back drilling hole, and the aperture is determined by the diameter of the back drilling hole and the preset different back drilling offset.
Furthermore, the test module further comprises an identification module, and the identification module is used for identifying the preset back drilling offset corresponding to each back drilling detection hole.
Furthermore, the test module can sequentially penetrate through the back drilling hole to observe the base materials around the back drilling detection hole corresponding to the back drilling hole according to the sequence of the preset back drilling offset from small to large, and when the base materials around the back drilling detection hole are observed through the back drilling hole, the offset of the back drilling hole is the preset back drilling offset corresponding to the back drilling detection hole.
The test module can also be used for sequentially observing the base materials around the back drilling detection hole according to the sequence of the offset from small to large and taking the preset back drilling offset corresponding to the back drilling detection hole capable of observing the base materials as the offset of the back drilling hole, so that the offset of the back drilling hole can be quickly and accurately determined, and the problems of large workload, time consumption, difficulty in judgment and the like caused by the alignment of the back drilling detection of the section detection can be effectively assisted.
Example 2
A method for detecting the depth of a back drilling plate is characterized by comprising the following steps:
s1, confirming the drilling depth: the back drilling of the early drilling needs to be carried out by slicing to confirm the drilling depth; so as to monitor the actual depth of the back drilling of the drilled hole, and the production plate can not be confirmed by 100 percent of slicing due to the complex grinding process and long grinding time of the slicing grinding process;
s2, 2 back drilling modules are designed and tested on the edge/technical edge of the PNL board, and the drilling depth condition of the back drilling hole can be judged by the testing modules through the on-off performance of electric testing.
Further, in step S2, a blind VIA hole diameter in the board is designed in each test module, the blind VIA hole diameter is communicated with the designed circuit and each layer of VIA aperture, the blind VIA hole distance is 1.2mm, and the line width is designed to be 6 mil.
Further, in the step S2, the blind bore diameter is 0.2mm larger than a bore diameter.
Further, in step S2, the size of the via hole is designed according to the size of the back drill hole-drill hole diameter.
Further, in step S2, a ring is designed at the outer layer via hole of each test module, the ring of the back drilling hole is 2mil larger than the single side of the back drilling hole, and the back drilling hole is 4mil larger than the single side of the back drilling hole.
Further, in step S2, each test module text layer is designed with a corresponding blind hole test character, the layer to be drilled by the back drill and the layer corresponding to the VIA aperture are required to be conducted, the character is required to be matched with the actual line layout, and the design depth of the drilling tape data is matched with the indication of the actual back drill layer number.
In the present invention, the detection method can be summarized as the following steps: adding a test module in a vacant area or a process edge of a PCB; after back drilling, the corresponding layer is disconnected with the VIA hole, the electrical test is not conducted, and the situation that the corresponding layer is drilled through is obtained; designing inner layer circuits, wherein each VIA hole corresponds to a corresponding layer; the outer layer characters are remarked with the corresponding inner layer layers communicated with the VIA holes.
Furthermore, the test module further comprises at least one back drilling detection hole which is arranged on the board edge of the printed circuit board and used for detecting the alignment of the back drilling, wherein the aperture of each back drilling detection hole is smaller than the diameter of the back drilling hole, and the aperture is determined by the diameter of the back drilling hole and the preset different back drilling offset.
Furthermore, the test module further comprises an identification module, and the identification module is used for identifying the preset back drilling offset corresponding to each back drilling detection hole.
Furthermore, the test module can sequentially penetrate through the back drilling hole to observe the base materials around the back drilling detection hole corresponding to the back drilling hole according to the sequence of the preset back drilling offset from small to large, and when the base materials around the back drilling detection hole are observed through the back drilling hole, the offset of the back drilling hole is the preset back drilling offset corresponding to the back drilling detection hole.
Example 3
A method for detecting the depth of a back drilling plate is characterized by comprising the following steps:
s1, confirming the drilling depth: the back drilling of the early drilling needs to be carried out by slicing to confirm the drilling depth; so as to monitor the actual depth of the back drilling of the drilled hole, and the production plate can not be confirmed by 100 percent of slicing due to the complex grinding process and long grinding time of the slicing grinding process;
s2, 2 back drilling modules are designed and tested on the edge/technical edge of the PNL board, and the drilling depth condition of the back drilling hole can be judged by the testing modules through the on-off performance of electric testing.
Further, in step S2, a blind VIA hole diameter in the board is designed in each test module, the blind VIA hole diameter is communicated with the designed circuit and each layer of VIA aperture, the blind VIA hole distance is 1.7mm, and the line width is designed to be 8 mil.
Further, in the step S2, the blind bore diameter is 0.2mm larger than a bore diameter.
Further, in step S2, the size of the via hole is designed according to the size of the back drill hole-drill hole diameter.
Further, in step S2, a ring is designed at the outer layer via hole of each test module, the ring of the back drilling hole is 2 mils larger than the single side of the back drilling hole, and the back drilling hole is 4 mils larger than the single side of the back drilling hole.
Further, in step S2, each test module text layer is designed with a corresponding blind hole test character, the layer to be drilled by the back drill and the layer corresponding to the VIA aperture are required to be conducted, the character is required to be matched with the actual line layout, and the design depth of the drilling tape data is matched with the indication of the actual back drill layer number.
In the present invention, the detection method can be summarized as the following steps: adding a test module in a vacant area or a process edge of a PCB; after back drilling, the corresponding layer is disconnected with the VIA hole, the electrical test is not conducted, and the situation that the corresponding layer is drilled through is obtained; designing inner layer circuits, wherein each VIA hole corresponds to a corresponding layer; the outer layer characters are remarked with the corresponding inner layer layers communicated with the VIA holes.
Furthermore, the test module further comprises at least one back drilling detection hole which is arranged on the board edge of the printed circuit board and used for detecting the alignment of the back drilling, wherein the aperture of each back drilling detection hole is smaller than the diameter of the back drilling hole, and the aperture is determined by the diameter of the back drilling hole and the preset different back drilling offset.
Furthermore, the test module further comprises an identification module, and the identification module is used for identifying the preset back drilling offset corresponding to each back drilling detection hole.
Furthermore, the test module can sequentially penetrate through the back drilling hole to observe the base materials around the back drilling detection hole corresponding to the back drilling hole according to the sequence of the preset back drilling offset from small to large, and when the base materials around the back drilling detection hole are observed through the back drilling hole, the offset of the back drilling hole is the preset back drilling offset corresponding to the back drilling detection hole.
The test module can also be used for sequentially observing the base materials around the back drilling detection hole according to the sequence of the offset from small to large and taking the preset back drilling offset corresponding to the back drilling detection hole capable of observing the base materials as the offset of the back drilling hole, so that the offset of the back drilling hole can be quickly and accurately determined, and the problems of large workload, time consumption, difficulty in judgment and the like caused by the alignment of the back drilling detection of the section detection can be effectively assisted.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art. It should be noted that the technical features not described in detail in the present invention can be implemented by any prior art in the field.
Claims (9)
1. A method for detecting the depth of a back drilling plate is characterized by comprising the following steps:
s1, confirming the drilling depth: the back drilling of the early drilling needs to be carried out by slicing to confirm the drilling depth;
s2, 2 back drilling modules are designed and tested on the edge/technical edge of the PNL board, and the drilling depth condition of the back drilling hole can be judged by the testing modules through the on-off performance of electric testing.
2. The method for depth inspection of back-drilled boards as claimed in claim 1, wherein in step S2, blind VIA holes are designed in each test module, the blind VIA holes are connected to the designed circuits and VIA holes on each layer, the blind VIA holes are spaced by 1.1-1.8mm, and the circuit line width is designed to be 5-9 mil.
3. The method for depth inspection of back drill plate according to claim 2, wherein the blind bore diameter is 0.2mm larger than a bore diameter in step S2.
4. The method for depth inspection of back-drilled board according to claim 2, wherein in step S2, the via hole size is designed according to the back-drilled hole-diameter size.
5. The method for depth detection of back-drilled boards according to claim 3, wherein in step S2, a ring is designed for each leading hole on the outer layer of the test module, the ring of the back-drilled hole is 2mil larger than the single side of the back-drilled hole, and the back-drilled hole is 4mil larger than the single side of the back-drilled hole.
6. The method for detecting the depth of the back-drill plate of claim 5, wherein in step S2, each text layer of the test module is designed with a corresponding blind-hole test character, the layer to be drilled by the back-drill for remark and the layer corresponding to the VIA aperture are required to be conducted, the character is required to be matched with the actual circuit wiring, and the design depth of the drill tape data is matched with the indication of the number of layers of the actual back-drill.
7. The method of claim 1, wherein the test module further comprises at least one back drill detection hole disposed on a board edge of the printed circuit board for detecting alignment of the back drill, wherein each back drill detection hole has a diameter smaller than a diameter of the back drill hole and each hole is determined by the diameter of the back drill hole and a preset different back drill offset.
8. The method of backdrilling board depth detection according to claim 7, wherein the test module further comprises an identification module for identifying a preset backdrilling offset corresponding to each of the backdrilling detection holes.
9. The method of claim 8, wherein the test module sequentially passes through the back drill holes to observe the substrate around the back drill detection hole corresponding to the back drill holes according to a preset back drill offset from small to large, and when the substrate around the back drill detection hole is observed through the back drill holes, the offset of the back drill holes is the preset back drill offset corresponding to the back drill detection hole.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010069872.9A CN111256578A (en) | 2020-01-21 | 2020-01-21 | Method for detecting depth of back drilling plate |
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| CN202010069872.9A CN111256578A (en) | 2020-01-21 | 2020-01-21 | Method for detecting depth of back drilling plate |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113280737A (en) * | 2021-05-14 | 2021-08-20 | 惠州中京电子科技有限公司 | Blind hole offset detection method for high-order HDI printed circuit board |
| CN113939081A (en) * | 2021-09-10 | 2022-01-14 | 珠海杰赛科技有限公司 | PCB structure capable of measuring back drilling depth and processing method thereof |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1174951A2 (en) * | 2000-07-17 | 2002-01-23 | Alcatel USA Sourcing, L.P. | System and method for providing high voltage withstand capability between pins of a high-density compliant pin connector |
| CN101876687A (en) * | 2010-06-04 | 2010-11-03 | 深南电路有限公司 | Test method for back drilling depth of PCB plate |
| CN201828238U (en) * | 2010-10-11 | 2011-05-11 | 深圳中富电路有限公司 | Back drill depth test device for back drill board |
| CN104284512A (en) * | 2013-07-09 | 2015-01-14 | 华通电脑股份有限公司 | Multi-layer circuit board with back drill depth detection structure and back drill depth monitoring method thereof |
| CN104567611A (en) * | 2013-10-25 | 2015-04-29 | 北大方正集团有限公司 | Method for detecting backdrilling depth |
| CN105657954A (en) * | 2014-12-03 | 2016-06-08 | 北大方正集团有限公司 | Back-drilling aligning detection module and method and PCB |
| CN205648192U (en) * | 2016-05-27 | 2016-10-12 | 胜宏科技（惠州）股份有限公司 | Communication backplate crimping hole back drilling degree of depth test module |
| CN205808341U (en) * | 2016-07-04 | 2016-12-14 | 深圳中富电路有限公司 | Machinery blind drilling depth test device |
-
2020
- 2020-01-21 CN CN202010069872.9A patent/CN111256578A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1174951A2 (en) * | 2000-07-17 | 2002-01-23 | Alcatel USA Sourcing, L.P. | System and method for providing high voltage withstand capability between pins of a high-density compliant pin connector |
| CN101876687A (en) * | 2010-06-04 | 2010-11-03 | 深南电路有限公司 | Test method for back drilling depth of PCB plate |
| CN201828238U (en) * | 2010-10-11 | 2011-05-11 | 深圳中富电路有限公司 | Back drill depth test device for back drill board |
| CN104284512A (en) * | 2013-07-09 | 2015-01-14 | 华通电脑股份有限公司 | Multi-layer circuit board with back drill depth detection structure and back drill depth monitoring method thereof |
| CN104567611A (en) * | 2013-10-25 | 2015-04-29 | 北大方正集团有限公司 | Method for detecting backdrilling depth |
| CN105657954A (en) * | 2014-12-03 | 2016-06-08 | 北大方正集团有限公司 | Back-drilling aligning detection module and method and PCB |
| CN205648192U (en) * | 2016-05-27 | 2016-10-12 | 胜宏科技（惠州）股份有限公司 | Communication backplate crimping hole back drilling degree of depth test module |
| CN205808341U (en) * | 2016-07-04 | 2016-12-14 | 深圳中富电路有限公司 | Machinery blind drilling depth test device |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113280737A (en) * | 2021-05-14 | 2021-08-20 | 惠州中京电子科技有限公司 | Blind hole offset detection method for high-order HDI printed circuit board |
| CN113280737B (en) * | 2021-05-14 | 2023-08-29 | 惠州中京电子科技有限公司 | Blind hole offset detection method for high-order HDI printed circuit board |
| CN113939081A (en) * | 2021-09-10 | 2022-01-14 | 珠海杰赛科技有限公司 | PCB structure capable of measuring back drilling depth and processing method thereof |
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Application publication date: 20200609 |