Electrical properties of rapid thermally annealed SiN_x:H/Si structures characterized by capacitance-voltage and surface photovoltage spectroscopy

Abstract

A comparative investigation of the characteristics of the SiN x :H/Si interface has been undertaken by capacitance-voltage measurements and surface photovoltage spectroscopy. By each of these techniques, we have determined the distribution of the interface trap density within the silicon bandgap. The samples were grown by the electron-cyclotron resonance plasma method starting from SiH 4 and N 2 as precursor gases whose flow ratio was varied to produce films of three different compositions: silicon rich, near stoichiometric and nitrogen rich. Post-deposition rapid thermal annealing treatments were applied to observe the evolution of interface properties with the annealing temperature in the range from 300 to 1050 • C. For thin dielectrics, the interface state density has a U-shaped distribution dominated by band-tail states. The minimum of this distribution decreases significantly and shifts to midgap for moderate annealing temperatures. For higher annealing temperatures, the trend is reversed. In the silicon-rich films, the percolation of rigidity caused by the chains of Si-Si bonds impedes the initial decrease of the defect density. For thicker films, the strain of the SiN x :H film produces a higher density of defects that results in increased levels of leakage currents and poorer electrical characteristics.

Effect of alloying temperature on the capacitance–voltage and current–voltage characteristics of low‐pressure chemical vapor deposition SiNx/n‐GaN MIS structures

“…The slightly lower D it of sample A may be owed to its low alloying temperature and associated chemical reactions during alloying, which will be discussed in the last. Actually, a similar phenomenon has been observed by others .…”

Characterization of nitrogen-rich silicon nitride films grown by the electron cyclotron resonance plasma technique

“…Films with N/Si ratios greater than 1.33 show good interface properties when used in silicon based MIS devices [18,21]. Additionally, nitrogen-rich films have been found to passivate the phosphorus vacancies in InP based MIS structures, allowing good interface properties without the deposition of an interface control layer [22,23,24].…”

Rapid thermally annealed plasma deposited SiNx:H thin films: Application to metal–insulator–semiconductor structures with Si, In0.53Ga0.47As, and InP

“…Furthermore, D it,min has no minimum for this composition and it can only be measured up to 500°C, showing a slightly increasing trend. 21 From Fig. 7, we see that in the N-rich films a reduction of Si DB of more than 1 order of magnitude occurs in coincidence with the reduction of D it,min .…”

“…14,18 On the other hand, when the release of hydrogen leaves unpassivated defects or causes a loss of nitrogen atoms, then a degradation of the performance is observed. 17 In this article, we analyze in detail the influence of the RTA on the physical properties of ECR deposited SiN x :H films in a wide range of compositions-from Si-rich films to N-rich-and analyze the RTA effects on the SiN x :H/semiconductor interface with Si, [19][20][21] In 0.53 Ga 0. 47 As, 22,23 and InP.…”