[OPTICAL REVIEW Vol. 12, No. 4 (2005) 345-351]
© 2005 The Optical Society of Japan
Novel High Precision Optoelectronic Device Fabrication Technique Using Guided Fluidic Assembly
Brahm Pal SINGH*, Kazutoshi ONOZAWA, Kazuhiko YAMANAKA, Tomoaki TOJO and Daisuke UEDA
Semiconductor Device Research Center, Semiconductor Company, Matsushita Electric Industrial Co., Ltd., 1-1 Saiwai-cho, Takatsuki, Osaka 569-1193, Japan
(Received October 18, 2004; Accepted January 26, 2005)
High precision assembly of laser diodes (LDs) on silicon wafer substrates for use in advanced optoelectronic devices is an important issue from a mass production point of view. An acceptable alternative to replace an obsolete pick and place flip chip bonding robotic technology with a simple, low cost and high speed technique is desired for industrial applications. We have investigated a novel assembling technique with micrometer order accuracy for LDs and other microchips. Its feasibility for rapidly assembling a large number of high power edge emitting LDs is practically demonstrated. A 150 μm thick nickel metal mask is used to confine as well as guide the unassembled LDs into the recesses by its restricted displacements. This technique is based on guiding the LDs within a suitable fluidic medium and the assembling process is performed in two steps: (i) coarse precision with a confinement mask to bring LDs near the recesses to achieve high assembling efficiency and (ii) fine precision due to the electrode patterns on the base surface of LDs, under fluidic as well as gravitational force. The assembly of 80 red LDs of the same size and of 40 pairs of red and infrared LDs of two different sizes is successfully demonstrated within less than ± 2 μm precision and 100% efficiency in a few seconds after transferring them into a confinement mask region.
Key words: Guided fluidic assembly, optical pick-up, laser diode, optical MEMS, optoelectronic devices
*E-mail address: singh.brahmpal@jp.panasonic.com