Dielectrics, deposition

Dielectric Deposition Systems. The most common techniques used for dielectric deposition include chemical vapor deposition (CVD), sputtering, and spin-on films. In a CVD system thermal or plasma energy is used to decompose source molecules on the semiconductor surface (189). In plasma-enhanced CVD (PECVD), typical source gases include silane, SiH, and nitrous oxide, N2O, for deposition of siUcon nitride. The most common CVD films used are siUcon dioxide, siUcon nitride, and siUcon oxynitrides. 

Dielectric deposition systems, in compound semiconductor processing, 22 192 Dielectric (radio frequency) dryers, 9 137-138... 

Figure 17.11. Process steps for forming Cu interconnects using the single damascene process (dielectric patterning) (a) planarized substrate (b) dielectric deposition (c) dielectric RIE through photoresist mask (d) etched insulator (e) deposition of diffusion barrier (Ta) and Cu seed layer (/) electrodeposition of Cu into a via (vertical interconnection) ( ) CMP of Cu excess Qi) patterning and deposition of Cu line (wire).

Figure 19.4. Through-mask deposition process (a) Si substrate (b) Cu seed layer deposition (c) photoresist deposition and patterning (d) through-mask electroless deposition of Cu (e) stripping of photoresist and etching of Cu seed layer outside line (f) dielectric deposition.

Fig. 36 Process steps for forming Cu interconnects using single damascene process (dielectric patterning) (a) substrate, (b) dielectric deposition,...

Oxidation Behavior Tungsten is susceptible to oxidation by oxygen at temperatures above 300°C. The reaction is not self-limiting and is enhanced because its forms W03 which is volatile at higher temperatures. Therefore, when tungsten is used as an interconnect material, precaution is needed to prevent oxidation especially during subsequent dielectric depositions. 

Wilk, G.D. Wallace, R.M. Electrical properties of hafnium silicate gate dielectrics deposited directly on silicon. Appl. Phys. Lett. 1999, 74,2854-2856. 

The high deposition temperature excluded the manufacturing of simple circuits using silicon nitride as gate dielectric for transistors with a metal gate electrode. Therefore, another gate dielectric, deposited at lower process temperatures, is necessary. 

Dielectric Deposit parylene-C Photo Etch Strip 200nm layer Via mask oxygen plasma Soak in stripper 10 min, Soak in fresh stripper 10 min, rinse, dry... 

MeV Li ion irradiation for AlSi/HfOj/n-Si MOS capacitors prepared at (a) 1, 10, and 100 kHz and (b) 500 kHz and 1 MHz. (From AmcZ. Instrum. Methods Phys. Res. Sect. B, 269(23), Singh, V., Shashank, N., Sharma, S.K., Shekhawat, R.S., Kumar, D., and Nahar, R.K., Frequency dependence studies on the interface trap density and series resistance of HfOj gate dielectric deposited on Si substrate Before and after 50 MeV ions irradiation, 2765-2770. Copyright 2011b, with permission from Elsevier.)... 

Dielectric deposition and metallization. Following completion of the front end, the individual devices are interconnected using a series of metal depositions and patterning steps of dielectric films (i.e., electric insulators). Current semiconductor fabrication includes as many as three metal layers separated by dielectric layers. 

Silicon Nitride (SiNj) - A silicon/nitrogen film dielectric deposited using plasma-enhanced or LPCVD. 

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