The optical segment deals with the design of semiconductor devices that interact optically with the environment, either where light is an input (such as optical sensors) or where light is an output (such as semiconductor lasers).

The primary areas are:

  • CMOS Image Sensors (CIS), a large business driven primarily by their use in digital cameras in smartphones, and to a lesser extent in high-end digital cameras and scientific applications
  • Charge Coupled Devices (CCD)
  • Solar cells, obviously driven by the use for renewable energy expected to increase significantly driven by parallel developments in battery technology
  • Silicon Photonics, such as edge-emitting and VCSEL lasers and waveguides, used largely in fiber optic communication systems

Silvaco’s product suite for CIS goes from TCAD, to SPICE modeling and simulation, up to custom layout and reliability analysis. Building on a foundation of TCAD the process itself can be built up and device analysis and optimization can be achieved. TCAD supports ray tracing, transfer matrix method simulation (TMM), finite different time domain simulation for optical simulation.

   
CMOS Image Sensor Simulation

 

CMOS Image Sensors are essentially complex analog designs that are a combination of an array of transistors and sense/control blocks that have a requirement of extremely high sensitivity. Since extracted CIS designs can get very large they require high accuracy and capacity simulation capabilities. There are a wide variety of PDKs available from various foundries that have CIS processes. Because CISs are typically mounted in some form of 3D packaging, running off a battery, and are often in physically restricted spaces, electromigration, IR drop analysis and especially thermal are extremely important and Silvaco’s suite of analysis tools can ensure the design of reliable devices.

CCD, solar cells, lasers and silicon photonics can be designed using Silvaco’s TCAD suite. Optical simulation including mode solver and laser whispering gallery mode can be used to simulate the interaction between the silicon and the light that is produced or absorbed.

 
Laser and Waveguide Simulation

 

Capabilities

TCAD
  • Ray Tracing
  • Transfer Matrix Method Simulation
  • Finite Difference Time Domain Simulation
  • Self-consistent Helmholtz solver
  • Strain-dependent k.p Model
  • Mode Solver
  • Laser Whispering Gallery
  • Robust Stable 3D Oxidation for CIS
SPICE Simulation
  • CIS SPICE Simulation
  • Golden SPICE Accuracy
  • Parallel SPICE extended for FastSPICE Applications
  • Large Extracted Post-layout Simulation
  • Transient Noise Analysis
Variation-Aware Design
  • High sigma analysis for CIS control, sense, array
  • Fast Monte Carlo analysis to save simulation runs; Local mismatch analysis for ADC
  • Statistical corners for quick design iterations
Custom Design
  • CIS Foundry PDK Support
  • Full Custom Layout
  • Integrated DRC/LVS
Extracted Netlist Analysis & Reduction
  • Parasitic Reduction
  • Design Analysis
  • Comparison of extracted netlist with parasitics
Invar
  • Block to Full-chip Level Analysis for CIS
  • Early layout IR/EM analysis
  • SPICE Accuracy
  • TSMC Certified