Wavelength Dependence of Photon-Induced Interface Defects in Hydrogenated Silicon Nitride/Si Structure during Plasma Etching Processes

Abstract

The wavelength dependence of SiN x :H/Si interface defect generation caused by vacuum ultraviolet (VUV)/UV radiation from plasma etching processes was investigated. VUV radiation (λ< 200 nm) had almost no impact on the generation of defects at the SiN x :H/Si interface, since all the radiation in this wavelength range was absorbed in the upper SiN x :H film. However, UV radiation (200 < λ< 400 nm) was able to reach the underlying SiN x :H/Si interface and damage the interface. Direct UV radiation reaching the SiN x :H/Si interface dissociated the chemical bonds at the interface and generated interface-trapped charges. The estimated total energy of absorbed photons (E total; 200 < λ< 400 nm) at the interface layer seems to be proportional to the interface-trapped charge density (D it) measured by capacitance–voltage measurement. However, the mechanism underlying the relationship between E total and D it is not yet clear. Visible radiation (λ> 400 nm) had no influence on damage generation on the SiN x :H/Si structure, since the visible radiation was transmitted through upper SiN x :H film and underlying interface layer. The results revealed that UV radiation transmitted through the upper dielectrics can cause the electrical characteristics of underlying metal–oxide–semiconductor (MOS) devices to fluctuate.

Incident ion dose evolution of damaged layer thickness in Si substrate exposed to Ar and He plasmas

“…One of the critical problems is plasma-induced damage [6][7][8][9] (PID), that is, undesirable defect creation inside the materials induced by plasma exposure. PID is mainly classified into three categories; 7,8) plasma-induced physical damage [10][11][12][13] (PPD) by ion bombardment, plasma-induced charging damage [14][15][16][17][18] (PCD) by conduction current, and plasmainduced radiation damage [19][20][21][22][23][24][25][26] (PRD) by high-energy photon irradiation. One should consider PID in designing plasma recipes and carrying out device simulations in the development of the present-day electronic devices because PID degrades the performance and reliability.…”

Characterization techniques of ion bombardment damage on electronic devices during plasma processing—plasma process-induced damage

“…27) In conjunction with an introduction of the so-called low-k films, the dielectric constant change after plasma exposure was discussed in many literatures. [59][60][61][62][63][64][65] This explored the extensive research of the PRD mechanism. Device structure-dependent, i.e.…”

Mechanism of wiggling enhancement due to HBr gas addition during amorphous carbon etching

“…The change in residual stress due to etching was reportedly caused by irradiation of ions, 16) vacuum ultraviolet (VUV) light, 15) and neutral species 17,18) delivered from plasma. They have been reported to degrade the irradiated surface [16][17][18][19][20][21][22][23] and generate residual stress on the surface (surface stress) in some cases. [16][17][18] Here, we discussed on the basis of a schematic view shown in Fig.…”