Hamamatsu-Photonics K.k.

Biosensor Laboratories Co., Ltd.

Hamamatsu Photonics Kabushiki Kaisha

Kazuhiro Atsumi

Kenshi Fukumitsu

Fumitsugu Fukuyo

Koji Kuno

Naoki Uchiyama

Tatsuya Suzuki

Kenichi Muramatsu

Toshimitsu Wakuda

Masayoshi Kusunoki

Ryuji Sugiura

Katsu Honzawa

Takeshi Sakamoto

Daisuke Kawaguchi

Takafumi Ogiwara

Tetsuya Osajima

Tsuyoshi Hayakawa

Masaharu Hoshikawa

Fumihiko Shimomura

Masayuki Masuko

Hiroyuki Iwaki

Seiji Kawaguchi

Hisaya Motojima

Masayoshi Kumagai

Yuichiro Sakamoto

Takafumi Tsunematsu

Etsuji Ohmura

Takahiko Ishiguro

Humihiko Shimomura

A laser processing method which can efficiently perform laser processing while minimizing the deviation of the converging point of a laser beam in end parts of an object to be processed is provided. This laser processing method comprises a preparatory step of holding a lens at an initial position set such that a converging point is located at a predetermined position within the object; a first processing step (Sand S) of emitting a first laser beam for processing while holding the lens at the initial position, and moving the lens and the ltd object relative to each other along a main surface so as to form a modified region in one end part of a line to cut; and a second processing step (Sand S) of releasing the lens from being held at the initial position after forming the modified region in the one end part of the line to cut, and then moving the lens and the object relative to each other along the main surface while adjusting the gap between the lens and the main surface after the release, so as to form the modified region.

Laser processing method and device

A laser processing method which can efficiently perform laser processing while minimizing the deviation of the converging point of a laser beam in end parts of an object to be processed is provided. This laser processing method comprises a preparatory step of holding a lens at an initial position set such that a converging point is located at a predetermined position within the object; a first processing step (Sand S) of emitting a first laser beam for processing while holding the lens at the initial position, and moving the lens and the object relative to each other along a main surface so as to form a modified region in one end part of a line to cut; and a second processing step (Sand S) of releasing the lens from being held at the initial position after forming the modified region in the one end part of the line to cut, and then moving the lens and the object relative to each other along the main surface while adjusting the gap between the lens and the main surface after the release, so as to form the modified region.

A laser processing method having a displacement acquiring step of acquiring a displacement between a point on the cutting line and one end of the cutting line in the object while irradiating the object with a second laser beam, converged by a lens, for measuring the displacement of a main surface of the object; and a position setting step of setting an initial position for holding the lens with respect to the main surface of the object according to the acquired displacement, and holding the lens at thus set initial position.

A converging point of processing laser light is made to accurately follow a laser light irradiation surface of an object to be processed. An object to be processedis irradiated with measuring laser light along a line to cut, astigmatism is added to a reflected light component of the measuring laser light reflected by a front faceof the objectirradiated with the measuring laser light, a displacement sensor signal corresponding to a converged light image of the reflected light component having the astigmatism added thereto is detected, and the displacement sensor signal is made to become a feedback reference value corresponding to the quantity of the reflected light component, so as to locate the converging point of the processing laser light at a predetermined position with respect to the front face. This allows tire converging point of the processing laser light to follow the front faceof the objectreliably and accurately even when an area exhibiting an extremely low reflectance to the measuring laser light exists in a part of the front faceand lowers the quantity of the reflected light component of the measuring laser light.

Laser working method

A laser processing method which can efficiently perform laser processing while minimizing the deviation of the converging point of a laser beam is provided. This laser processing method comprises a displacement acquiring step (Sto S) of irradiating an object to be processed with a rangefinding laser beam for measuring a displacement of a main surface of the object while converging the laser beam with a lens and acquiring the displacement of the main surface along a line to cut while detecting reflected light reflected by the main surface in response to the irradiation; and moves the processing objective lens and the object relative to each other along the main surface, while adjusting the gap between the processing objective lens and the surface according to the displacement acquired by the displacement acquiring step, thereby forming the modified region along the line to cut.

A method of cutting an object to be processed comprises the steps of irradiating an object to be processed with a laser light which is an elliptically-polarized light having an ellipticity other than 1 such that a direction of polarization of the laser light intersects a line to cut the object and a thickness direction of the object, while locating a converging point of the laser light within the object, so as to form a modified region within the object along the line and generate a fracture from the modified region in the thickness direction of the object, and causing the fracture to reach front and rear faces of the object so as to cut the object along the line.

Method of cutting object to be processed, method of cutting strengthened glass sheet and method of manufacturing strengthened glass member

A modified region is accurately formed at a desirable position with respect to a laser light irradiation surface of an object to be processed. When an average difference &#x3b3; has a value exceeding a predetermined threshold during trace recording, a particle segment Z including a line segment S where the average difference &#x3b3; exceeds the predetermined threshold is defined. This determines that a particle exists on a line to cutand randomly reflects measuring laser light, whereby a segment where the presence of the particle affects a control signal in a line segment to cut is detected as the particle segment Z. Correcting the control signal in the particle segment Z inhibits a converging lens from moving more than necessary because of an error included in the signal value under the influence of the presence of the particle, thus allowing the converging point of the processing laser light to accurately follow a front face

Laser processing method for cutting planar object

An object to be processedis irradiated with laser light L with a standard pulse waveform, so as to form a molten processed region, which has a larger size in the thickness direction of the objectand is easy to generate a fracturein the thickness direction of the object, within a silicon wafer, and with laser light L with a retarded pulse waveform, so as to form a molten processed region, which has a smaller size in the thickness direction of the objectand is hard to generate the fracturein the thickness direction of the object, within a silicon wafer.

Laser processing method and laser processing system

Method of cutting object to be processed

While a converging lensis relatively moved along a lineincluding a line to cut, measuring laser light Lis converged with the lenswhen the lensis positioned on a processing regionhaving an outer shape between an object to be processedand a frame, and a reflected light component of the laser light Lreflected by a front faceof the objectis detected. While keeping a substantially constant distance between the front faceand the lenssuch that a converging point P of processing laser light Lis positioned at a constant distance from the front faceaccording to the detection, the laser light Lis converged by the lens, so as to form a molten processed regionwithin the object

Laser processing method for forming a modified region in an object

A laser processing method which can accurately cut an object to be processed along a line to cut is provided. A modified regionformed by multiphoton absorption forms a cutting start regionwithin an object to be processedalong a line to cut. Thereafter, the objectis irradiated with laser light Labsorbable by the objectalong the line to cut, so as to generate fracturesfrom the cutting start regionacting as a start point, whereby the objectcan accurately be cut along the line to cut. Expanding an expandable filmhaving the objectsecured thereto separates individual chipsfrom each other, which can further improve the reliability in cutting the objectalong the line to cut

Laser beam machining method

A laser processing apparatus comprises a converging lensfor converging processing laser light and rangefinding laser light Ltoward a wafer, an actuator for actuating the lens, a shaping optical systemfor adding astigmatism to reflected light Lof the rangefinding laser light, a quadrant photodiodefor receiving the reflected light Land outputting voltage values corresponding to its light quantities, and a controller for regulating the actuator, and positions a converging point Pof the rangefinding laser light Lbetween a focal point Pof the lens and the lens, so as to make it possible to form a modified region at a position deeper from the front face, thereby suppressing adverse effects due to the reflected light L. The control is based on an arithmetic value subjected to a division by a sum of the voltage values, so as to prevent the arithmetic value from being changed by the quantity of reflected light.

Laser material processing system

A wafer having a front face formed with a functional device is irradiated with laser light while positioning a light-converging point within the wafer with the rear face of the wafer acting as a laser light incident face, so as to generate multiphoton absorption, thereby forming a starting point region for cutting due to a molten processed region within the wafer along a line. Consequently, a fracture can be generated from the starting point region for cutting naturally or with a relatively small force, so as to reach the front face and rear face. Therefore, when an expansion film is attached to the rear face of the wafer by way of a die bonding resin layer after forming the starting point region for cutting and then expanded, the wafer and die bonding resin layer can be cut along the line.

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Hamamatsu, Japan

Kazuhiro Atsumi