ALD Market Heats Up Applied Materials
Atomic Layer Deposition (ALD) can be described as a process that deposits materials at the atomic level, layer by layer, and that enables thin and conformal films on devices. Applied Materials is a new entrant to the ALD market and hopes to make headway within a competitive and fragmented environment.
Though ALD has been in use since the 1970s, it became popular at 45nm, when Intel used the process to deposit hafnium, a high-k material, for a transistor’s gate stack. High-k replaced silicon dioxide, which in turn enabled chipmakers to scale their devices, keeping the industry on Moore’s Law, which notes that the number of transistors in a dense integrated circuit has doubled approximately every two years.
While the deposition of high-k materials for logic remains an important application for ALD, this is only a small part of the ALD market. Whether the process is thermal or plasma enhanced, ASMI estimates that the total ALD tool market for semiconductor applications will reach $1.2 billion over the next three or four years, up from $600 million in 2014.
Despite the strong market competition, Applied Materials believes that there is room for more if it maintains its focus on such things as patterning, capacitor dielectrics and 3D NAND. Applied Materials is selling a spatial-based ALD tool, in addition to furnace/batch and single-wafer tools. The new spatial tool eliminates the purging process, thereby boosting ALD productivity. Other emerging ALD markets include interconnects, fin doping, ReRAMs and selective deposition.
ASM International, Lam Research, Tokyo Electron (TEL), Ultratech and others are also increasing their ALD efforts, because the applications for ALD are rapidly expanding. The industry is in a race to develop selective deposition, which combines novel chemistries with ALD and involves a process of depositing materials and films in exact places.
Other big applications for ALD are 3D NAND and multi-patterning for logic. Cutting-edge 3D NAND chips have 48 layers and as 3D NAND scales above 48 layers, the specs will become accordingly tighter and more precise. ALD, therefore, must improve in order to meet the challenge.
ALD is becoming more important for chip production and shows great potential, because it is a good methodology for achieving increasingly complicated, thin and conformal films while retaining quality.