Michael Lebby4th IEEE Workshop on AST 1 Tutorial 1998 Optoelectronic Devices and Packaging: VCSEL Technology Tutorial Leader: Michael Lebby Phoenix Applied Research Center Motorola 2100 East Elliot Road, Tempe, Az Voice: (602) & fax 4952 Tutorial Objective Introduction Tutorial Objective Optoelectronic devices and packaging have found increasing use in many new products over the last 20 Yrs. This tutorial primarily will focus on semiconductor laser based technology with particular emphasis on emerging new technologies such as the Vertical Cavity Surface Emitting Laser (VCSEL) and how to take advantage of its uniqueness in packaging. The tutorial will look at the driving factors required for low cost high volume VCSEL based packages and what impact they will have in tomorrows products. As there are many packaging solutions for VCSEL based technology proposed, the course will show the relative merits of popular new technologies with respect to high volume and low cost manufacturing. PHOENIX APPLIED RESEARCH CENTER PARC Michael Lebby Jan98 PHOENIX APPLIED RESEARCH CENTER PARC Michael Lebby Jan98

Michael Lebby4th IEEE Workshop on AST 2 Tutorial Objective Providing information that gives the attendee a working knowledge on: –Commercial Edge Emitter laser technology –What a EE laser chip is and looks like –How a EE laser chip is packaged –VCSEL technology: why the euphoria –What a VCSEL chip is... –How VCSELs are packaged... –VCSEL Performance –VCSEL Applications... today...tomorrow –Technical Challenges –Commercial and market impact Section 1 –VCSEL Technology –Device Status –Package Status Section 2 –VCSEL Technical Issues –Fabrication and Characterization –Testing and Reliability –Manufacturing PHOENIX APPLIED RESEARCH CENTER PARC Michael Lebby Jan98

Michael Lebby4th IEEE Workshop on AST 3 Abbreviation: VerticalCavitySurfaceEmittingLaser VCSEL (commonly pronounced 'vixel') Other names used: Veesel (V-SEL) VCSELD (V-seld) VCL (Vixel) Surface Emitter Micro-resonator

Michael Lebby4th IEEE Workshop on AST 4 Why VCSELs over Edge Emitters (EEs) ? Component Cost Impact Fabricated like LEDs -> first laser with potential die cost to approach LEDs (with high volume) Wafer probing, no cleaving, GaAs saw, surface light emission VCSELs in high volume markets the die cost will be similar to CD laser chips as the cost is in the package Die cost is sensitive to real estate (VCSEL advantage) Epi wafer costs are more for VCSEL (EE advantage) Only if the package, probe, aligment procedures are made LED-like will the VCSEL hope to reach the low cost levels expected Packaging Cost Impact Low volume fiber optics markets EE package cost is 80-90% package VCSEL should reduce this through simplified packaging/coupling/KGD High volume markets requires passive alignment and KGD before package VCSEL has potential to achieve these goals with less volume than the EE Trend towards LED-like packaging means plastic alternatives are needed System Cost Impact VCSEL packages are smaller -> smaller systems VCSEL has lower power drain -> longer battery life on systems VCSEL can be flip-chip packaged -> lower cost systems VCSEL has circular output beam -> less lenses in systems VCSEL Arrays are natural -> provides degree of freedom in design EE Laser and VCSEL Output Characteristics Edge emitting laser VCSEL Auto-power control (can the VCSEL avoid it?)

Michael Lebby4th IEEE Workshop on AST 5 VCSEL Device Status Structures Planar Proton Implanted Index Guided Ridge Waveguide Hybrid Mirror Intracavity contact Lateral Oxide Native Oxide Wafer Fused What is commercially available today? Proton Implanted Ridge Waveguide Common device Cross-sections Proton Isolated Planar VCSEL Ridge Wave Guide VCSEL

Michael Lebby4th IEEE Workshop on AST 6 After: R.Schneider (1995) Partial dielectric mirror and partial semiconductor mirror After: R.Morgan (1995) Visible VCSEL structure

Michael Lebby4th IEEE Workshop on AST 7

Michael Lebby4th IEEE Workshop on AST 8 Small signal modulation of a lateral oxide confined VCSEL After: B.Thibeault, UCSB

Michael Lebby4th IEEE Workshop on AST 9 Native oxide mirror VCSEL After: M.H.MacDougal (1995) After: J.J.Dudley (1994) Wafer fused structure for long wavelength VCSEL

Michael Lebby4th IEEE Workshop on AST 10 Commerical VCSEL Status After: Strategies Unlimited 1996 VCSEL Package Status Packages that are being used for VCSELs TO-can wire-bond Plastic Leadframe Flip-chip TAB Flip-chip C4 Flip-chip Efforts to address VCSEL arrays have been the focus of many R&D labs over the last 5Yrs A few examples are discussed Companies participating include: AMP, Gore Photonics, MITEL, HP, Honeywell, IBM, Lucent, Micro-optical, Picolight, SDL, Vixel, Xerox amongst others. Motorola's parallel link is productized 10channels, 300m) Integrated (Simplify Packaging) Detector Lens