Hitachi Seiko, Ltd.

Hitachi Via Mechanics Ltd.

Kunio Arai

Yasuhiko Kanaya

Hiroshi Aoyama

Hiroaki Ashizawa

Hiromi Nishiyama

Haruo Akahoshi

Tamio Otani

Hiroyuki Sugawara

Kazuhisa Ishii

Kazunori Hamada

Toshinori Kawamura

Hiromi Nishiyawa

Yasuhiko Kita

Yasushi Ito

Kenji Suzuki

Hideo Ueno

Kazuhiro Kogure

Humio Watanabe

Yasuhiko Kanaga

In a method of manufacturing a printed wiring board, a via reaches from a surface copper layer to an inner-layer copper layer of a multilayer board, and copper layers and insulating layers are alternately layered. The wiring board is machined by a laser, and a process of machining the via includes forming a laser absorbing layer on a surface of a copper layer disposed on the surface of the multilayer board. The laser is irradiated, and an electrolytic etching and removal of the laser absorbing layer is carried out in this order.

Method for manufacturing printed wiring board and electrolytic etching solution for use in the manufacturing method

There is provided a laser machining method and a laser machining apparatus whose machining accuracy and quality excel without lowering machining efficiency. One hole is machined by a split beam that is a first pulsed laser beam and another split beam that is a second pulsed laser beam whose irradiation position is determined based on irradiation position of the first laser beam. In this case, the machining quality may be improved by machining the circular hole by equalizing circling directions and angular velocity of the split beams. A beam splitter splits a laser beam outputted out of one laser oscillator into the split beams and AOMs can time-share them.

Laser machining method and laser machining apparatus

A method and an apparatus for perforating a printed circuit board are provided so that the processing efficiency and the board densification can be improved. In test processing, a conductor layeris irradiated with a pulsed laser beamwhose energy density is set at a value high enough to process the conductor layerwhile emissionfrom a processed portion is monitored. Thus, the number of pulses of irradiation required for processing a window in the conductor layeris obtained. An insulating layeris irradiated with a pulsed laser beamwhose energy density is set at a value high enough to process the insulating layerbut low enough not to process a conductor layer+1 under the insulating layer. Thus, the number of pulses of irradiation required for processing a window in the insulating layeris obtained. The conductor layeris irradiated with the laser beamthe obtained number of pulses of irradiation, and the insulating layeris irradiated with the laser beamthe obtained number of pulses of irradiation. Thus, a hole is processed in the printed circuit board.

Method and apparatus for perforating printed circuit board

A printed circuit board fabrication method allows a fabrication time and a fabrication cost to be reduced. The fabrication method of the printed circuit board includes steps of forming a resist layer on a surface of the printed circuit board whose surface is made of an insulator, of forming a hole that is connected from the surface of the resist layer to a conductor pattern of an inner layer and a hole and grooves having a depth not connected with the conductor layer of the inner layer by irradiating lasers, of filling a conductive material into the holes and the grooves to form a conductor pattern and of removing the resist layer to project a portion of the conductor pattern out of the surface of the insulating layer.

Fabrication method of printed circuit board and printed circuit board machining apparatus

A laser machining method and a laser machining apparatus by which holes excelling in form accuracy can be machined efficiently are to be provided. A first cylindrical lens and/or a second cylindrical lens to correct any deformation of reflective face of a first mirror and/or a second mirror is arranged on an optical axis of a laser beam, and converging positions of the laser beam for an X-component and for a Y-component are coincident with a point on the optical axis.

There is provided a method for removing molten and scattered Cu and overhang that are generated around a via opening during laser machining in a direct laser via forming method of directly machining an outer-layer copper foil. In a manufacturing method of a printed wiring board of machining the via by laser directly through the copper foil of a copper-clad laminate in which the copper foil is clad on a base material resin, a process for machining the via is carried out in a sequence of (a) a copper foil surface treatment step of forming an oxide film on the surface of said copper foil, (b) a laser via machining step, (c) an alkali treatment step and (d) a molten and scattered Cu etching step. It is desirable to carry out (e) a de-smearing treatment after the molten and scattered Cu etching.

Manufacturing method of printed wiring board as well as copper-clad laminate and treatment solutions used therefor

Method and apparatus for laser perforating printed circuit board

A laser machining method and a laser machining apparatus superior in hole position accuracy and hole quality. An outgoing beam outputted as short pulses is shaped by a pulse shaping unit so as to form a #1 branch beam. The #1 branch beam is supplied to a portion to be machined, so as to machine the portion. In this case, the #1 branch beam may be controlled to synchronize with the outgoing beam. When a piece to be machined is made from a metal material and at least one of an organic material and an inorganic material, the metal material is machined with a laser beam shaped to have a pulse width not shorter than 100 ns, and at least one of the organic material and the inorganic material is machined with a laser beam shaped to have a pulse width shorter than 100 ns.

Provided is a multi-beam laser drilling apparatus for drilling a workpiece, simultaneously at two positions while telecentric errors are suppressed, in which a conventional optical system in which galvanometer mirrors are used for a first laser beam, and a galvanometer-mirror system is located close to an f&#x3b8; lens in order to prevent occurrence of telecentric error. A second laser beam which has been deflected by a second galvanometer-mirror system, transmits through a polarized beam mixers and is incident upon the first galvanometer-mirror system and the f&#x3b8; lens, and accordingly, the workpiece is drilled simultaneously at two positions with the use of both first and second laser beams.

Multibeam laser drilling apparatus

An improved method and apparatus for drilling blind via holes to connect between upper conductive layers and lower conductive layers of printed wiring boards with laser lights. The resin layer contacting the targeted conductive layer is drilled to remain the residual layer with laser lights, and the residual layer is removed with a UV laser beam whose energy density is lower than the decomposition energy threshold of the conductive layer and higher than that of the resin layer. The apparatus for this drilling has at least two laser paths. The spatial energy distributions are made top-hat-shaped with beam homogenizer units in the paths, and the diameters and the energy densities are adjusted independently.

Method and apparatus for drilling printed wiring boards

Beam distributing/shaping units and the number of which is the same as the number of heads and are disposed in series with each other on an optical path of a laser beam radiated from a laser oscillator Then, the beam distributing/shaping units and are operated so that a laser pulse is supplied to one of the heads which has been positioned. By selecting the timing for operating the beam distributing/shaping units and , the laser beam having energy the magnitude of which is substantially fixed is supplied to a portion to be machined. Thus, the laser oscillator is used effectively, and the machining energy is controlled accurately so that a high-quality hole can be machined.

Laser beam machining and laser beam machine

The invention provides a method and an apparatus of making a hole in a printed circuit board, which improve the quality of a hole shape and the processing speed. In accordance with the invention, a control apparatus controls a laser oscillator and a galvano mirrors so as to form a hole while gradually reducing a pulse width in each step with respect to one hole. As a result of this, no insulating material is left on the bottom portion of the hole, and it is possible to make a hole having an intended shape, particularly, having a desired diameter of the hole bottom.

Method and apparatus of making a hole in a printed circuit board

The apparatus is for spot-facing for exposing an inner-layer conductor embedded in an insulator of a printed circuit board. The spot-facing removes the entire insulator by a mechanical cutter, except a remaining part thereof, to a position just above the inner-layer conductor. The remaining part of the insulator is smaller in thickness than the insulator removed by the mechanical cutter. Then, the remaining part of the insulator is removed by scanning the part with a laser beam to expose the inner-layer conductor. The laser beam is in a slender (elongated) shape almost perpendicular to the scanning direction of the laser beam and has an almost uniform energy density along the slender shape. Cutter processing is sufficient to be done before the inner-layer conductor, and there is no fear of damaging the inner-layer conductor. Moreover, it is easy to control thermal influence on the portion of the circuit board to be processed by the laser beam, because the energy density of the laser beam is almost uniform. Therefore, the product yield according to the processing is improved.

Apparatus for laser processing with a mechanical cutter

An improved drill bit for high speed, small diameter drilling of printed circuit boards uses flute/land ratio tapering in combination with the appropriate web thickness and point, cutting or flute angles to obtain high quality, accurately positioned holes. In one embodiment, the web thickness at the tip is 15% of the drill diameter, the flute/land ratio is 2.0, the tip angle is 130.degree., the second cutting angle is 20.degree., the third cutting angle is 30.degree., the flute angle is 32.degree., the relief groove depth is 0.001', body length is 0.256' and the distance between the body end and the flute end is 0.01'. Such a bit is used in connection with an air jet cooling/cleaning system and a step feed drilling method wherein the first step is between four-six times drill diameter, the second step is between two-three times the drill diameter, and the third step and subsequent steps are between 1.5-2.5 times the drill diameter.

Drill bit and step feeding method

The disclosure relates to spot-facing for exposing an inner-layer conductor embedded in an insulator of a printed circuit board. The spot-facing removes the entire insulator by a mechanical cutter, except a part thereof, to a position just above the inner-layer conductor. The part of the insulator is smaller in thickness than the insulator removed by the mechanical cutter. Then, the remaining part of the insulator is removed by scanning the part with a laser beam to expose the inner-layer conductor. The laser beam is in a slender shape almost perpendicular to the scanning direction of the laser beam and has an almost uniform energy density along the slender shape. Cutter processing is sufficient to be done before the inner-layer conductor, and there is no fear of damaging the inner-layer conductor. Moreover, laser-beam processing is easy to control thermal influence on the portion to be processed of the circuit board, because the energy density of the laser beam is almost uniform. Therefore, the product yield according to the processing is improved.

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Atsugi, Japan

Kunio Arai