OSE6615C - Optoelectronic Device Fabrication Laboratory

Design and micro-fabrication of semiconductor optoelectronics devices including passive waveguides, light emitting diodes (LEDs), laser diodes (LDs), photodetectors and electro-optic modulators.

This is a single semester course designed to strengthen the knowledge base of graduate students in the fabrication methods of modern optoelectronic semiconductor devices. Hands-on fabrication of several optoelectronic devices will be accompanied by classroom lectures designed to provide necessary background knowledge of the fabrication process. Students are expected to gain the general skill set needed to fabricate many of the modern semiconductor devices that are commercially manufactured today.

Credit Hours

• 3.0 hours

Prerequisite

• Graduate Standing or Consent of Instructor

Required References

• Class Notes/Handouts (provided by instructor)

Course Outline

Lab 1: Clean Room

• Chemical Safety Review
• Cleanliness (Clean room class, effect of particles on fab process)
• Gowning Area
• Clean room Apparel (Hair net, gown, gloves, goggles, respirator, shoe cover)
• Clean room Paper & Pen
• Chemical Storage (Acid, Base, Solvent, Photoresist)
• Clean room Equipment (Fume hood, Aligner, Microscope, Temescal, RTA, MBE, LEICA, Oxide Etcher, III-V Etcher, PECVD, AFM, Stepper, Furnace, Oven, Dice Wire Bonder, Flip Chip Bonder, Sputter tool, Profilometer)
• Fabrication Basics Steps (Photolithography, etching, metal deposition, thin film deposition/growth, Test, Packaging)
• The Flow of Device Fabrication

Lab 2: Fume Hood Operations

• Chemical Safety and Fume Hood (Chemical vapors)
• Clean room Worker Toolbox (Metal/ carbon tipped tweezers, razor blades, cotton/foam swabs, etc)
• Types of wafers (GaAs, Si, GaN/Sapphire/SiC, InP)
• Wafer Handling and Cleaving (Material hardness, crystal planes)
• Cleaning Procedure (Acetone, Methanol, Isopropanol, DI Water)
• Operating the Spin Coater Tool
• Operating the Hotplate
• Photoresist and Thickness (Photolithography, dry etching, passive optoelectronics devices)
• Scratch Test
• Generate Spin Vs. Thickness Curve
• Cleaning the Fume Hood
• Solvent Disposal

Lab 3: Photolithography

• S1813 Photoresist (Material datasheet, positive/negative photoresist, etc)
• Aligner Operation (Lamp, min. feature size, measuring lamp power, calculating exposure time, etc)
• Mask
• 351 Developer (Over/under development)
• Photolithography Steps (Spin, soft bake, exposure, PEB, developing, hard bake)
• Generate Depth Vs. Exposure Time Curve
• Generate Depth Vs. Exposure Dose Curve

Lab 4: Etch

• Wet vs. Dry Etch
• Sidewalls (Isotropic, anisotropic, directional)
• Chemical Safety and Acids (MSDS review, special protective apparel)
• Mixing chemicals (Order, percentage, molarity)
• Etching
• Operating the Profilometer
• Generate Etch Rate Vs. Acid Concentration Curve
• Acid Disposal

Lab 5: Metal Deposition & Contact Annealing

• Contacts (n/p contacts, substrate dependence, transparency in optoelectronics, ohmic vs. schottky)
• Review of Metal Deposition Techniques
• Operating the Temescal (E-beam Evaporator)
• Contact annealing
• Operating the RTA
• Generate Contact Resistance Vs. Temp (or Time) Curve

Lab 6: GaAs LED

• n-metal deposition and contact annealing (1 week)
• Photolithography, p-contact deposition, and lift-off (1 week)
• Manual wafer probe testing

Lab 7: InP Photodetector

• n-metal deposition and contact annealing (1 week)
• Photolithography and Device Mesa Etch (1 week)
• Photolithography, p-contact deposition, and lift-off (1 week)

Lab 8: Packaging and Testing

• Dicing wafers (LEDs and Detectors)
• Mounting Devices onto Headers
• Operating the Convection Oven
• Operating the Wire Bonder
• Measure L-I-V curve, Dark current, and Responsivity