Laser-induced forward transfer as a potential alternative to pick-and-place technology when assembling semiconductor components

Abstract

Fabrication technologies for the semiconductor industry have enabled ever smaller electronic components but now face a fundamental limit in their assembly. As the components get smaller and smaller, the difficulty of assembly increases. At the same time, the number of components per circuit board area is growing, as is the case with LED displays. This in turn calls for an increasing assembly rate. The conventional pick-and-place method can handle approximately 25–30 thousand dies per hour but has increasing limitations when component dimensions are reduced below 150 μm edge length. Laser-induced forward transfer is used as a potential alternative for an assembly of semiconductor components. This technique allows to transfer semiconductor components with an edge length of less than 150 μm to a target substrate. The current process is contactless, damage-free, and has sufficient placement accuracy. If this process is combined with the property of high-pulse repetition rates, it is possible to significantly increase the assembly rate of semiconductor components compared to the current limitations. The aim of this study is to characterize the flight properties of silicon semiconductor components of various dimensions in a laser-driven transfer process using optical imaging methods. This method allows to analyze velocity, the direction of fall, and acceleration of falling components. The results can be used to analyze the transfer behavior of various component sizes and to make estimates of the stability of the transfer process.

Structuring of thin films by ultrashort laser pulses

“…LIFT is a powerful and flexible technique that is capable to transfer solid layers as well as "soft materials" (including liquid phases). LIFT of metals (e.g., aluminum [145], chromium [146][147][148], gold [149], nickel [150], platinum [151], titanium [146], tungsten [152], and vanadium [153]), semiconductors [154], dielectrics (Al 2 O 3 [155], InO x [156], V 2 O 5 [157], ZnO [158]), and high-temperature superconductors [159] was reported. The method was also used for the printing of organic thin-film transistors [160], organic micro-capacitors [161], and organic light-emitting diodes [160,162].…”

Facile Modification of Flexible Electrodes via Laser Transfer

“…Laser-induced forward transfer (LIFT) is a simple process, where a pulsed laser beam is focused through a transparent substrate (i.e., donor substrate) onto a thin layer (donor layer) [ 20 , 21 , 22 , 23 ]. Each laser pulse allows the precise and well localized transfer of the donor layer as a pixel (with different shapes, areas and thicknesses) on a rigid or flexible substrate (receiver substrate) that is placed parallel, in contact to or at short distance from the donor.…”

Transfer characteristics for laser-induced forward transfer of stainless steel particle

“…A LIFT method that uses a target powder on a sacrificial layer has also been reported. [8][9][10] This method utilizes laser absorption of the sacrificial layer, which makes it difficult to reuse the substrates. Laser cleaning (LC) is an established technology in which laser irradiation is used to move a granular material.…”