A laser processing method for a substrate with a device formed on a front surface thereof and including an electrode pad, the method including: a laser beam applying step of applying the laser beam to the back surface of the substrate to form a fine hole in the substrate at a position corresponding to the electrode pad; a detecting step of detecting first plasma light emitted from the substrate at the same time that the fine hole is formed in the substrate by the laser beam applied thereto, and second plasma light emitted from the electrode pad; and a laser beam irradiation finishing step of stopping application of the laser beam when the second plasma light is detected in the detecting step. A peak power density of the laser beam to be applied is set in a range from 175 GW/cm.sup.2 or less to 100 GW/cm.sup.2 or more.

A laser processing method for applying a laser beam to the reverse side of a substrate with a device formed on a face side thereof and including an electrode pad, to form a pore in the substrate that leads to the electrode pad, includes an irradiation area setting step of detecting the size of the electrode pad and setting an irradiation area for the laser beam such that the pore to be formed is positioned within the electrode pad. After the irradiation area setting step has been performed, the laser beam is applied to the reverse side of the substrate to form a pore in the substrate at a position corresponding to the electrode pad. First plasma light emitted from the substrate and second plasma light emitted from the electrode pad are detected. When the second plasma light is detected, the beam is stopped from being applied to the substrate.

A laser processing method for processing a substrate having a device formed on the front side, an electrode pad being formed on the device. The method includes applying a pulsed laser beam to the back side of the substrate at a position corresponding to the electrode pad, thereby forming a fine hole in the substrate so that the fine hole reaches the electrode pad, detecting first plasma light generated from the substrate by the application of the pulsed laser beam to the substrate and also detecting second plasma light generated from the electrode pad by the application of the pulsed laser beam to the electrode pad, and stopping the laser beam when the second plasma light is detected. Time intervals of the pulsed laser beam repeatedly applied to the same fine hole are set to 0.1 ms or more.

A laser processing method for a wafer includes: linearly forming a plurality of shield tunnels each having a fine hole and an amorphous region surrounding the fine hole at predetermined intervals in an inner part of a test substrate, the test substrate having a material and a thickness identical to those of a substrate of the wafer to be processed, while changing time intervals of a plurality of pulses constituting a burst pulse laser beam; and measuring a rupture strength when the test substrate is ruptured along the plurality of shield tunnels. Next, the time intervals of the pulses when the rupture strength is at a minimum are calculated, and a laser processing step is performed which linearly forms a plurality of shield tunnels at predetermined intervals in an inner part of the wafer, by irradiating the wafer with the laser beam having the time intervals of the pulses.

A laser processing method for a wafer includes: linearly forming a plurality of shield tunnels each having a fine hole and an amorphous region surrounding the fine hole at predetermined intervals in an inner part of a test substrate, the test substrate having a material and a thickness identical to those of a substrate of the wafer to be processed, while changing time intervals of a plurality of pulses constituting a burst pulse laser beam; and measuring a rupture strength when the test substrate is ruptured along the plurality of shield tunnels. Next, the time intervals of the pulses when the rupture strength is at a minimum are calculated, and a laser processing step is performed which linearly forms a plurality of shield tunnels at predetermined intervals in an inner part of the wafer, by irradiating the wafer with the laser beam having the time intervals of the pulses.

Disclosed are apparatus and methods related to ground paths implemented with surface mount devices to facilitate shielding of radio-frequency (RF) modules. In some embodiments, a method for fabricating a radio-frequency module includes providing a packaging substrate, the packaging substrate configured to receive a plurality of components and the packaging substrate including a ground plane. In some embodiments, the method includes mounting a surface mount device on the packaging substrate, and forming or providing a conductive layer over the surface mount device such that the surface mount device electrically connects the conductive layer with the ground plane to thereby provide radio-frequency shielding between first and second regions about the surface mount device.

Disclosed are apparatus and methods related to ground paths implemented with surface mount devices to facilitate shielding of radio-frequency (RF) modules. In some embodiments, a method for fabricating a radio-frequency module includes providing a packaging substrate, the packaging substrate configured to receive a plurality of components and the packaging substrate including a ground plane. In some embodiments, the method includes mounting a surface mount device on the packaging substrate, and forming or providing a conductive layer over the surface mount device such that the surface mount device electrically connects the conductive layer with the ground plane to thereby provide radio-frequency shielding between first and second regions about the surface mount device.

A method for fabricating a printed circuit, comprising: darkening a surface location of a conductive material with one or more ultrafast pulses of laser radiation and ablating the conductive material at the surface location with one or more longer duration pulses of laser radiation to produce traces or micro via patterns on the surface of a PCB. A hole for a blind micro via is produced by ablating the conductive material at the darkened surface location with one or more longer duration pulses of laser radiation and cleaning a second conductive material under the substrate with one or more further longer duration pulses of laser radiation.

A radio-frequency (RF) module is disclosed to include a packaging substrate configured to receive a plurality of components. The RF module also includes a surface mount device (SMD) mounted on the packaging substrate, the SMD including a metal layer that faces upward when mounted. The RF module further includes an overmold formed over the packaging substrate, the overmold dimensioned to cover the SMD. The RF module further includes an opening defined by the overmold at a region over the SMD, the opening having a depth sufficient to expose at least a portion of the metal layer. The RF module further includes a conformal conductive layer formed over the overmold, the conformal conductive layer configured to fill at least a portion of the opening to provide an electrical path between the conformal conductive layer and the metal layer of the SMD.

A radio-frequency (RF) module is disclosed to include a packaging substrate configured to receive a plurality of components. The RF module also includes a surface mount device (SMD) mounted on the packaging substrate, the SMD including a metal layer that faces upward when mounted. The RF module further includes an overmold formed over the packaging substrate, the overmold dimensioned to cover the SMD. The RF module further includes an opening defined by the overmold at a region over the SMD, the opening having a depth sufficient to expose at least a portion of the metal layer. The RF module further includes a conformal conductive layer formed over the overmold, the conformal conductive layer configured to fill at least a portion of the opening to provide an electrical path between the conformal conductive layer and the metal layer of the SMD.