Using wafer scale optics, wafer scale integration, and wafer level packaging of image sensor, we developed small form
factor (3.3mmx3.3mmx2.5mm), low manufacturing cost, Pb-free solder reflow compatible digital camera modules which
are suitable for many applications including mobile electronic devices, automotives, security, and medical applications.
System alignment is often the cost driver in the production of optical system. In order to both miniaturize and reduce production costs, wafer scale integration of active and passive components is required. This integration relies on a host of techniques to align and bond active and passive devices into a monolithic structure. Moreover, this initial packaging is accomplished while the optics and supporting structures are in wafer form, thereby providing parallel fabrication with resultant cost savings. This paper describes the fundamental techniques for producing IMOS from wafer scale substrates. The relative merits of each approach are discussed, along with design concerns for successful application. Two example systems are discussed, each using a different fabrication technique.
Silicon v-groove structures have been utilized for passive positioning of optical fiber for fiber optic and opto- electronic applications. In this paper, we will present our results of using micro-machined silicon v-groove arrays to passively align optical fiber arrays to micro rod optics. We will also demonstrate the integration of N fiber arrays bonded into the silicon v-groove with a 1xN micro lens array, which is composed of a 2 inch-phase level diffractive optics. For the assembly of 1x6 fiber array and lens array with 16 phase level diffractive optics, the experimental results indicated that total insertion loss per link is typically 1.5-2.0 dB/channel.
Anisotropically etched v-grooves on silicon substrate for the positioning of optical fibers have been widely implemented in fiber optics and optoelectronic applications. Because the anisotropic etching depends upon the crystallographic orientation of silicon, the v-grooves are normally formed parallel to the <110> direction. However, some applications, such as optical switches, and wavelength division multiplexing/demultiplexing devices, fan-in and fan-out configuration for fiber positioning are required. In this paper, we will report a single mode refractive plate switch where a micromachined silicon waferboard was implemented for passively positioning optical fibers. We successfully demonstrated a 2 X 2 single mode optical switch with less than 0.64 dB loss.
Penetration into the fiber-in-the-loop (FITL) and fiber-to-the-curb (FTTC) markets requires a drastic cost reduction in optoelectronic packaging. To achieve this goal, passive alignment techniques were developed using micromachined silicon waferboard technology which showed great potential for the tight tolerances (plus or minus 0.5 micrometers) required to passively align optoelectronic devices to single mode fibers. In this technology, micromachined alignment pedestals and standoffs precisely locate the x, y, and z positions of optoelectronic devices, which have matching alignment notches, to the optical fiber confined by a v-groove. The tight tolerances are possible using precision photolithography and well controlled reactive ion etching (RIE). In this paper, we report our process development results of forming micromachined silicon alignment pedestals using RIE. We demonstrate RIE etch depth control for the 6 micrometer z-standoffs with a 0.13 micrometer standard deviation and etch profile control for the x and y alignment pedestals to within 0.25 micrometers for each edge, which were obtained across a 3-inch wafer and from run to run. Such high precision control on RIE etch profile and uniformity is extremely important in developing manufacturable processes.