CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of S.G. Provisional Application No. 10201902757X filed on Mar. 27, 2019, the disclosure of which is herein incorporated by reference in their entireties for all purposes.

FIELD OF THE INVENTION

The present disclosure relates to packaging of devices. In particular, the present disclosure relates to alignment carriers and an alignment system having a camera module configured for aligning dies or devices on the alignment carrier for die bonding.

BACKGROUND

Panel level packaging (PLP) of devices have garnered significant interest in recent years. This is due to the larger volume of dies which can be packaged in parallel compared to conventional wafer level or substrate level packaging techniques. PLP involves attaching individual dies on a large carrier for die bonding. For example, the dies are arranged in a matrix on the carrier, with rows and columns of dies. The panel, depending on its size, can accommodate significantly more dies than on a wafer, for example, 3 times to 5 times or more dies than a wafer. This increases packaging throughput as well as reducing costs.

An important consideration in PLP is the precise positioning of the die on the panel prior to bonding at a target location. Conventionally, bonding locations are calculated based on global reference marks on the panel and each die is placed in a predetermined position by precise mechanical movement of a bonding head.

However, conventional PLP techniques suffer from positioning errors on the carrier. Positioning errors may occur due to various reasons, such as geometry related issues (e.g., straightness, linearity, and orthogonality), temperature issues (e.g., expansion of scales, slides, and distortion) and vibration issues (e.g., high-speed motion over long distances may result in stopping position errors). In addition, during the reconstruction or reconstitution process, the carrier and panel (dies with molding) undergo thermal cycles of expansion and contraction. Additional thermal cycles may be experienced due to reuse of the carriers.

Panel distortion causes geometry or size to vary from the original design from which the die locations are calculated. The more thermal cycles experienced, the greater the distortion. The distortion problem is further exacerbated as the panel size increases. Distortion causes displacement of dies on the panel from the original calculated locations. Displacement of dies negatively affects the yield of the bonding process, increasing costs. The greater the distortion, the greater the displacement. The greater the displacement, the greater the negative effects on yields and costs. Due to the displacement errors, subsequent processes involve significant error mitigation to construct the circuits more accurately

From the foregoing discussion, it is desirable to provide PLP with high accuracy throughout the bonding process to increase yields as well as to improve scalability.

SUMMARY

Embodiments of the present disclosure generally relate to devices. In particular, the present disclosure relates to die bonding using an alignment carrier. The alignment carrier may be employed for die bonding of single die packages or multiple die packages, such as multi-chip modules (MCMs). The die bonding is facilitated by a die bonding tool with a camera or an alignment module configured to align dies for bonding onto the alignment carrier.

In one embodiment, a device includes an alignment carrier for die bonding which includes a planar carrier and die bond regions defined on the planar carrier. Each die bond region of the planar carrier includes local alignment marks for use in die bonding.

In one embodiment, an alignment system for a die bonder includes an integrated camera module configured to view downward in a vertical direction for detecting local alignment marks of a die bond region of interest of an alignment carrier with die bond regions having local alignment marks when the alignment carrier is mounted on a base assembly of the die bonder. The integrated camera module is further configured to view upwards in the vertical direction for viewing a bottom surface of a die when attached to a bond head of the die bonder for die bonding. The system further includes an alignment controller for receiving input from the camera module, the alignment controller is configured to align the die when attached to the bond head to the die bond region of interest for die bonding based on the input from the camera module.

In one embodiment, a method for die bonding includes providing an alignment carrier including die bond regions defined thereon. The die bond regions include local alignment marks to facilitate aligning dies for die bonding of the dies to the die bond regions and the alignment carrier is mounted onto a base assembly of a die bonder. The method further includes picking up a first die for die bonding onto a first die bond region on the alignment carrier by a bond head of the die bonder and aligning the first die to the first die bond region using an alignment system. The alignment system is configured to view downward in a vertical direction for detecting local alignment marks of the first die bond region, and to view upwards in the vertical direction for viewing a bottom surface of the first die. The method further includes sending information of the alignment system to a controller which aligns the first die to the first die bond region based on the information from the alignment system. The method continues to include moving the first die downwards vertically by the bond head to the alignment carrier after alignment of the first die to the first die bond region is achieved to bond the first die on the first die bond region of the alignment carrier.

These and other advantages and features of the embodiments herein disclosed, will become apparent through reference to the following description and the accompanying drawings. Furthermore, it is to be understood that the features of the various embodiments described herein are not mutually exclusive and can exist in various combinations and permutations.

