Ultralarge-scale integration

As indicated above, the goal in recent years in the ultralarge-scale integrated-circuit (ULSI) industry has been to reduce contamination on surfaces to below the level detectable with state-of-the-art equipment. For economic and environmental reasons, this method had to be replaced by one referred to as just clean enough. This requires that action-reaction relationships be identified between contaminants and... 

NMOS and PMOS (p-channel MOS) transistors are used side by side in complementary metal-oxide-semiconductor (CMOS) technology to form logic elements. These structures have the advantage of extremely low power consumption and are important in ultralarge-scale integration (ULSI) and very-large-scale integration (VLSI) (13). 

Note These specifications were developed at Balazs Analytical Laboratory. Abbreviations are defined as follows DRAM, dynamic random access memory VLSI, very-large-scale integration ULSI, ultralarge-scale integration TOC, total oxidizable carbon THM, trihalomethane SEM, scanning electron microscopy and EPI, epifluorescence... 

Treichel H, Frausto R, Srivastan S, Whithers B. Process optimization of dielectrics chemical-mechanical planarization processes for ultralarge scale integration multilevel metallization. J Vac Sci Technol A 1999 17.4 1160-1167. 

As can be deduced from the frequent mention of dielectric constants in sections about properties of CVD polymers in this review, a majority of CVD polymers are targeted towards low dielectric constant interconnect applications in ultralarge scale integrated circuits (ULSI). The urgent need to develop a suitable material and process for this application can be sensed by the sheer number of papers published in this area. For an in-depth understanding, the reader is referred to some excellent review articles in literature. "" ... 

Rankin, S.E., Malanoski, A.P. and Van Swol, F., Materials Research Society Symposium Proceedings 636 (Nonlithographic and Lithographic Methods of Nanofabrication From Ultralarge-Scale Integration to Photonics to Molecular Electronics) D1.2/1-D1.2/6, Boston, 2001. 

The alloy W-lOTi is used as a sputtering target in the manufacture of microelectronics devices, such as VLSI, ULSI (very large resp. ultralarge-scale integration), and DRAM (dynamic random access memory) chips. Thin W-Ti layers are sputtered onto silicon substrates and act as a diffusion barrier against aluminum (intercormect). 

All liquids contain vast numbers of submicrometer-sized particles that are too small to be visible but that can be detected and counted with high-sen-sitivity apparatus. Chemicals used on industrial processing of ultralarge-scale integration devices must be essentially free from these particles and suitable filtration membranes are available with porosities as low as 0.01 pm. It is to be expected that use of these filters will make significant improvement to the chemical purity of the product. In acids and ammonia solution, many trace metal impurities are present in the form of submicrometer particles and ultrafiltration in a suitable clean enviromnent is useful for improving reagents intended for trace analysis at levels of pg per kg and lower. 

T. Homma, Low Dielectric Constant Materials and Methods for Interlayer Dielectric Films in Ultralarge-Scale Integrated Circuit Multilevel Interconnects Mater. Set Eng., 1998,23,243. 

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