The Materials Preparation and Characterization Laboratory specializes in creating and analyzing semiconductor materials and nanostructures—the tiny building blocks that power modern electronics and photonics.

Our core work involves III-V semiconductors (materials made from elements in columns III and V of the periodic table, like gallium arsenide), which are essential for high-speed electronics and advanced light-based technologies.

We harness these special materials to create:

• Nanomembranes: Ultra-thin, flexible sheets of semiconductor material.
• 3D Self-Forming Objects: Structures that spontaneously roll or fold into complex three-dimensional shapes, often used to create microscopic optical devices.
• Optical Emitters and Photonic Structures: Devices that efficiently produce or control light, which are crucial for lasers, LEDs, and future optical circuits.

We also focus on integrating different materials into these nanostructures to unlock new and enhanced unctionalities.

1. Rolled-Up Nanotubes and Micro-Optics

We are experts in rolling up our ultra-thin materials into nanotubes or microtubes. These tiny cylinders can act as highly efficient photonic structures—miniature light traps or resonators—that have potential applications in advanced sensors and communication.

2. Precision Growth: Molecular Beam Epitaxy (MBE)

We use a sophisticated technique called Molecular Beam Epitaxy (MBE) to grow perfect, atomic-layer-by-atomic-layer III-V heterostructures (layered materials). This technique gives us ultimate control over the material's properties.

• Virtual Substrates: We have pioneered a method where we use released III-V nanomembranes as virtual substrates to build even more complex and higher-quality layered structures on top.
• Self-Assembled Structures: Our work also includes growing naturally forming structures like self-assembled quantum dots (tiny semiconductor islands that act like artificial atoms) and using techniques like local droplet etching to create nanoscale patterns.

Characterization

To ensure our materials are perfect, we use a suite of powerful characterization tools:

• X-ray Diffraction (XRD): This technique uses X-rays to precisely measure the spacing and quality of the atomic layers in our structures.
• Atomic Force Microscopy (AFM): Like a record player, the AFM uses a tiny needle to map the surface topography of our materials at the nanoscale.
• Scanning Electron Microscopy (SEM): The SEM uses a beam of electrons to create highly detailed, high-magnification images of the material’s surface structure.
• Photoluminescence (PL) Measurements: This essential technique helps us understand how efficiently our materials emit light, which is critical for their application in optical devices.