faster read-out for digital-cinema cameras, and 3D imaging for gaming. These markets are placing ever increasing functionality and performance demands on today’s image sensors, which are in turn delivering an exponential rate of growth in both complexity and performance to ensure they can keep pace. 3D imagers are becoming a very hot R&D topic given the current
push toward 3D entertainment. Increasing R&D investment is predicted in automotive imaging, and for 3-D range-finding and time-of-flight (TOF) increases in integrated logic functionality are driving a dramatic increase in features.
forthcoming years for applications. Rapid imager functions and
Memory design has seen a number of trends over the years: process technology has steadily reduced its minimum feature size; a wide variety of techniques have been developed to improve packing-density; and a myriad of technology/circuit/system optimizations have been created to improve performance and reduce power dissipation. In addition, emerging technologies such as 3D chip stacking and new physical memory mechanisms are pushing the memory R&D frontier even-further forward. Some current state-of-the-art results from ISSCC 2011 include:
28nm 64Gb TLC NAND flash memory
7Gb/s-GDDR5 DRAM with 2Gb capacity
64Mb SRAM in High-κ Metal-Gate 32nm SOI technology with robust operation
28nm SRAM using 6T cells with low-voltage 0.6V operation
Emerging memory technologies realizing non-volatile RAM: FeRAM (Ferrolectric RAM) with a novel sensing scheme, a fast read/write RRAM (Resistive RAM), and a large bandwidth CBRAM (Conductive-Bridging RAM) at 2.3GB/s.
NON-VOLATILE MEMORY (NVM)
The performance of persistent Non-Volatile RAM (NVRAM) has evolved over time, with ISSCC faithfully tracking these developments over the years. ISSCC 2011 will report the highest read/write bandwidths for emerging NVRAM technologies such as Phase Change Memory (PCRAM) and Resistive RAM (RRAM) resulting from the use of new circuit and device technology (Figure 5). This is presenting new opportunities for extending the memory technology spectrum, together with existing NAND/MRAM/FeRAM/PCRAM technologies, as shown in Figure 6. Commercial uses of these new breeds of NVRAM have been very slow to appear because of the rapid reduction of per-bit costs of conventional flash memory technologies already in the market. However, these new technologies are sure to capture some specific markets for lower-power or zero stand-by system implementation in the coming age of green technology.