Disco Corporation

International Business Machines Corporation

Sumitomo Bakelite Company Limited

Shigefumi Okada

Richard Francis Indyk

Jae-Woong Nah

Yuki Watanabe

Ian D Melville

Shunsuke Teranishi

Satoru Katsurayama

Kenta Onishi

Shuichiro Tsukiji

Yuki Ikku

Hiroyuki Urabe

Nobumori Ogoshi

Kimitake Mantoku

Daisuke Oka

A wafer processing method for forming a modified layer within a wafer along planned dividing lines forms the modified layer within the wafer, positions a condensing point within the wafer or at a top surface of the wafer and applies a second laser beam while moving the condensing point, images reflected light, and determines a processed state of the wafer on the basis of an imaged image. The second laser beam is formed such that a sectional shape of the second laser beam in a plane perpendicular to a traveling direction of the second laser beam is not axisymmetric with respect to an axis along the planned dividing lines.

Wafer processing method

A substrate includes a plurality of semiconductor chips arranged in a grid pattern and laterally spaced from one another by channel regions. The substrate includes a vertical stack of a semiconductor layer and at least one dielectric material layer embedding metal interconnect structures. The at least one dielectric material layer are removed along the channel regions and around vertices of the grid pattern so that each semiconductor chip includes corner surfaces that are not parallel to lines of the grid pattern. The corner surfaces can include straight surfaces or convex surfaces. The semiconductor chips are diced and subsequently bonded to a packaging substrate employing an underfill material. The corner surfaces reduce mechanical stress applied to the metal interconnect layer during the bonding process and subsequent thermal cycling processes.

Stress-resilient chip structure and dicing process

A transfer unit transferring a wafer from or to a cassette is provided. The transfer unit includes a holding portion holding the wafer under suction and a driving portion moving the holding portion. The holding portion includes a body, a plurality of suction openings formed on the upper surface of the body so as to be spaced from each other, a vacuum transmitting passage connected to a vacuum source for transmitting a vacuum from the vacuum source to the suction openings, and a plurality of suction pads provided at the suction openings, each suction pad being formed of an elastic material. The suction openings are spaced from each other in the radial direction of the wafer, and the suction pads are selectively provided at any desired ones of the suction openings.

Transfer unit including suction openings configured to receive suction pads or seal members therein

During the performance of a laser processing step of applying a laser beam to a wafer to form modified layers inside the wafer respectively along division lines, a predetermined one of the modified layers already formed is imaged by a camera from the back side of the wafer with predetermined timing, and a positional deviation of the predetermined modified layer from the corresponding division line is detected to calculate a correction value. Then, the correction value is added to data on applied position of the laser beam to thereby make the applied position of the laser beam coincide with each division line. Accordingly, a positional deviation of the modified layer to be formed after this correction from each division line can be suppressed.

Laser processing method for workpiece

In one embodiment, a dielectric material layer embedding metal structures is ablated from the chip-containing substrate by laser grooving, which is performed on dicing channels of the chip-containing substrate. Subsequently, an underfill layer is formed over the dielectric material layer in a pattern that excludes the peripheral areas of the chip-containing substrate. The physically exposed dicing channels at the periphery can be employed to align a blade to dice the chip-containing substrate. In another embodiment, an underfill layer is formed prior to any laser grooving. Mechanical cutting of the underfill layer from above dicing channels is followed by laser ablation of the dicing channels and subsequent mechanical cutting to dice a chip-containing substrate.

Wafer dicing employing edge region underfill removal

Growing community of inventors

Tokyo, Japan

Shigefumi Okada