IMAGING Infrared

Today, Time-of-Flight (ToF) systems are among the most innovative technologies offering imaging companies an opportunity to lead the market. Every major player wants to integrate these devices to provide functions such as 3D imaging, proximity sensing, ambient light sensing and gesture recognition. Sony / Softkinetic has been investigating this technology deeply, providing a unique pixel technology to several image sensor manufacturers in three application areas: consumer, automotive and industrial. For industrial applications, Sony/Softkinetic has licensed its technology to Texas Instruments, which is providing ToF imagers for human detection or robot-human interaction.

The OPT8241 3D ToF imager is packaged using Chip-On-Glass (COG) technology. The device comprises a system-on-chip (SoC) and glass filter in the same component in thin, 0.7 mm-thick, packaging.

This report analyzes the complete component, from the glass near-infrared band-pass filter to the collector based on ToF pixel licenses developed by Sony/Softkinetic and adapted by Texas Instruments. The report includes a complete cost analysis and price estimation of the device based on a detailed description of the package, and the ToF imager.

It also features a complete ToF pixel technology comparison with the Infineon/pmd, STMicroelectronics and Melexis automotive ToF imagers, which are all also based on Sony/Softkinetic technology, with details on the companies’ design choices.

Overview / Introduction

Texas Instruments Company Profile and Time of Flight Technology

Physical Analysis

• Physical Analysis Methodology
• Package
• View and dimensions
  • Package opening
  • Package cross-section: optical filter, RDL, bumps
• Image Die
  • View, dimensions and marking
  • Die overview: active area, CPAD technology
  • Die delayering, main block ID and process
  • Cross-section: metal layers, pixel
  • Process characteristics

ToF Pixel Physical Comparison with Infineon, STMicroelectronics, Melexis Automotive ToF Image Sensor

• Package, Pixels, Filters

Manufacturing Process Flow

• Overview
• ToF Imager Front-End Process
• ToF Imager Wafer Fabrication Unit
• Packaging Process Flow
• Final Assembly Unit

Cost Analysis

• Cost Analysis Overview
• The Main Steps Used in the Economic Analysis
• Yield Hypotheses
• ToF Imager Die Cost
  • Front-end cost
  • Back-end: tests and dicing
  • Wafer and die cost
• Component
  • Packaging cost
  • Packaging cost by process step
  • Component cost

Estimated Price Analysis

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