Puvaneswaran ChelvanathanP65212

Principal Supervisor: Professor Dr. Nowshad Amin

Transmission Electron Microscopy (TEM)

Basic Principles & Application in Thin Film

Photovoltaic Materials

Presentation Outline

Introduction : Limitation of Visible Light Microscopy (VLM) Electron Wave-Like Nature TEM Components & Working Principle TEM Image Generation Interpretation of TEM ImagesApplication in PV Research Field TEM Facility : Hi-Tech Ltd. Conclusion

Limitation of Light Microscopy

Resolution Illustration

Diffraction Barrier Phenomena

Visible Light & λ

“ It is a poor comfort to hope that human ingenuity will find ways and means of overcoming this limit”

Abbe’s Diffraction Limit :

20 years later…….

Particle-Wave DualityP.E K.E

Taking Relativistic Effect into account:

Accelerating Voltage Vs. λ

Light Vs. Electrons

Wave-Matter Interaction

Introduction to Electron Microcopy

Optical vs. TEM vs. SEM vs. CRT

TEM Working Principle

Electron Gun

Electron Gun Types

Electron Gun Types

Electron Lens

Electron Lens

Optical Lens vs. Electron Lens

Principle of Electron Lens

Electron Beam Alignment

Electron Beam Focusing

Imaging: “Seeing The Electrons”

Imaging vs. Diffraction Pattern (DP)

Imaging : Bright Field vs. Dark Field

Imaging : Bright Field vs. Dark Field

Imaging : Bright Field

Imaging : Bright Field

Diffraction Pattern

Diffraction Pattern

Diffraction Pattern

Diffraction Pattern

Diffraction Pattern

Diffraction Pattern

Application in PV Device/Materials

Application in PV Device/Materials

Application in PV Device/Materials

Application in PV Device/Materials

Application in PV Device/Materials

Application in PV Device/Materials

Application in PV Device/Materials

TEM Facility : Hitech, Puchong

Some Results…. MoS2

Some Results…. MoS2

XRD vs. SAED

XRD SAED

Conclusion

TEMFundamental Limitation of VLMTEM Main components & operating principlesImage generation: BF, DF and DP Interpretation of DP Application in PV research

Jeol Electron Microscopy 1.25 MeV HVEM

* RemarksTopics Not covered:

TEM Sample Preparation

Convergent Beam Electron Microscopy (CBED) Analytical Electron Microscopy (AEM) - Electron Energy Loss Spectroscopy (EELS) - Cathodoluminescence (CL)