Laser transfer articles and method of making

Abstract

The present invention is directed to methods for transferring pre-formed electronic devices, such as transistors, resistors, capacitors, diodes, semiconductors, inductors, conductors, and dielectrics, and segments of materials, such as magnetic materials and crystalline materials onto a variety of receiving substrates using energetic beam transfer methods. Also provided is a consumable intermediate comprising a transfer substrate and a transfer material coated thereon, wherein the transfer material may be comprised of pre-formed electronic devices or magnetic materials and crystalline materials that may be transferred to a variety of receiving substrates. Aspects of the present invention may also be used to form multi-device electronic components such as sensor devices, electro-optical devices, communications devices, transmit-receive modules, and phased arrays using the consumable intermediates and transfer methods described herein.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application is a divisional application of U.S. application Ser. No. 10 / 935,461 filed Sep. 7, 2004, which claims priority to U.S. Provisional Application Ser. No. 60 / 500,795 filed Sep. 5, 2003, both applications are incorporated herein by reference in their entirety.REFERENCE TO GOVERNMENT INTEREST[0002]This invention was made with Government support under contracts DASG60-02-C-0039 and DAAH01-03-C-R223 awarded by the U.S. Army Space and Missile Defense Command and U.S. Army Aviation and Missile Command. The Government has certain rights in this invention.BACKGROUND OF THE INVENTION[0003]Fabrication in the semiconductor and electronics industries relies on material transfer techniques. Semiconductor device transfer, for example, may be accomplished by a process of mounting and mechanically dicing semiconductor wafers to singulate the devices, followed by a device transfer step using a robotic “pick-and-place” system.[0004]Another pro...

AI Technical Summary

Benefits of technology

[0028]In one embodiment, individual devices (e.g. transistors, resistors, or capacitors) or circuits are formed or placed on a substrate that is preferably transparent to a source of energy. In contrast to the transfer steps, which transfer a pre-formed device, the devices themselves may be fabricated by conventional semiconductor processing techniques. Once fabricated, the devices may be placed onto a transfer substrate. As such, this fabrication of the devices may be carried out prior to the transfer steps, without the processing concerns related to fabrication on a flexible or curved substrate. As such fabrication of the electronic devices is efficient and inexpensive as compared to fabrication on a flexible substrate. Final transfer of a pre-formed device onto a flexible, rigid, or curved receiving substrate, which was not involved in the fabrication, may thus be accomplished by the transfer, without any damage to the receiving substrate. The fabrication may employs a higher resolution beam than the beam from the energy source used to subsequently transfer the formed devices.

[0031]Embodiments of the present invention obviate the need for multi-step material deposition and post-deposition processes to fabricate devices on flexible polymeric substrates, such as building transistors in layer-by-layer fashion (e.g., channel material, then implantation, then source and drain electrodes, then gate dielectric, etc.) on the substrate. Rather, the invention exploits established, high-volume, low-cost fabrication techniques used for building high-performance pre-fabricated devices. The invention simply transfers these pre-fabricated devices onto to a variety of substrates. The pre-fabricated devices may be commercially available silicon, GaAs, or other wafers with transistors or other electronic components. These transistors or other electronic elements can now be “punched” out of rigid substrates (e.g., wafers) and “printed” onto flexible substrates. In contrast to fluidic self-assembly techniques, the present invention facilitates liquid-free transfer of high-performance devices to a variety of substrates on which the device materials could not have originally been deposited and processed. These devices show higher performance than devices currently being pursued for use in flexible electronics (e.g., those based on organic semiconductors and polycrystalline or laser-recrystallized silicon).

Problems solved by technology

However, this process relies on statistics and requires special equipment.

Because the film material is vaporized by the action of the laser, laser induced forward transfer is inherently a homogeneous, pyrolytic technique and typically cannot be used to deposit complex crystalline, multi-component materials or materials that have a crystallization temperature well above room temperature because the resulting deposited material will be a weakly-adherent amorphous coating.

Moreover, because the material to be transferred is vaporized, it becomes more reactive and can more easily become degraded, oxidized or contaminated.

The method is not well suited for the transfer of organic materials, since many organic materials are fragile and thermally labile and can be irreversibly damaged during deposition.

For example, functional groups on an organic polymer can be irreversibly damaged by direct exposure to laser energy.

Other disadvantages of the laser induced forward transfer technique include poor surface-coverage uniformity, morphology, adhesion and resolution.

Further, because of the high temperatures involved in the process, there is a danger of ablation or sputtering of the support which can cause the incorporation of impurities in the material that is deposited on the receiving substrate.

Another disadvantage of laser induced forward transfer is that it typically requires that the coating of the material to be transferred be a thin coating, generally less than 1 micron thick.

Because of this requirement, it is very time-consuming to transfer more than very small amounts of material.

A disadvantage of this method is that, because many materials were present on the laser-transparent substrate, it is difficult to achieve a highly homogeneous coating of the material of interest.

Integrated circuit (IC) devices with these feature sizes (and associated high-performance) cannot be fabricated using direct write technologies.

A pick and place system can only transfer one device at a time, and cannot handle putting devices across a large area with high accuracy.

Because the costs of fabricating / building on a flexible or curved substrate are very high, there remains a need to transfer a pre-formed device onto a flexible or curved substrate as a late-stage processing step.

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