Silicon Epitaxial Growth by a Fast Wafer Rotating Reactor Using Silane Gas

For the utilization of high-electron-mobility transistor (HEMT) devices fabricated on GaN on Si structure as high-power devices, deep pits, which are known as inverted pyramid-shaped defects formed in the surface of a HEMT structure, are critical because they act as leakage pathways and degrade the breakdown property. We investigated in detail the origin of pits in the HEMT structure with a strained-layer superlattice (SLS). The pits were found to emerge from rotation domains, in which the crystal structure rotates around the c-axis, in the AlN buffer layer. The analysis by ultra low voltage scanning electron microscopy (ULV-SEM) revealed that the domains were formed on dense Al regions in Al preseeding layer. By optimizing Al pre flow conditions, we eliminated dense Al regions in Al preseeding layer, consequently, no rotation domains in the AlN buffer layer. An extremely low pit density of the HEMT structure with fine breakdown property was successfully achieved.

Section: Introductionmentioning

confidence: 99%

Origin and suppression of critical deep pit in high-electron-mobility transistor structure using GaN on Si technology with strained-layer superlattice

Miyano¹,

Tsukui²,

Nago³

et al. 2018

“…6) Satoh and coworkers reported the consistent theoretically derived growth rate with the experimental growth rate obtained using a carefully designed reactor that gives uniform inlet gas flow. [7][8][9][10] However, their experiment was carried out only for 2 or 3 inch wafers. They did not report the number of particles adhering onto a wafer surface for large-diameter wafers.…”

Section: Introductionmentioning

confidence: 99%

Newly Developed High-Speed Rotating Disk Chemical Vapor Deposition Equipment for Poly-Si Films

Terai

Kobayashi

Katsui

et al. 2005

New measurements of the zero-energy elecuon yield in the region of lhe pholodouble ionization threshold in helium are presented. showing for the first time a Wanniertype cusp with a small asymmetry of the excitltiodionimtion wing amplitudes, similar to the el&" impact results in the region of the first ionization threshold. The observed pressure dependence of the cusp amplitude asymmelry a d other second-order effects are discussed in nn attempt to explain the discrepancy with the earlier photoionization results of Hall et al.

“…12) Satoh and coworkers reported a theoretically derived growth rate is consistent with the experimental growth rate obtained by a carefully designed reactor that gives a uniform inlet gas flow. [13][14][15][16] However, their experiment is only for 2-or 3-in. wafers, and they did not examine an in-situ doping process.…”

Section: Introductionmentioning

confidence: 99%

High-Speed Rotating-Disk Chemical Vapor Deposition Process for In-Situ Arsenic-Doped Polycrystalline Silicon Films

Terai

Kobayashi

Katsui

et al. 2005

We have developed high-speed rotating-disk chemical vapor deposition (CVD) equipment for polycrystalline silicon (poly-Si) films. This CVD equipment has an enhanced ability to reduce the boundary layer thickness at a given temperature above a wafer surface, and to suppress vapor-phase reactions. We investigated in-situ arsenic-doped poly-Si film deposition using silane (SiH4), arsine (AsH3) and nitrogen (N2) in a high-speed rotating-disk CVD as functions of AsH3 flow rate and deposition temperature. Both the deposition rate and resistivity decreased with increasing AsH3 flow rate. A deposition rate of 120 nm/min, a resistivity of 16 mΩ·cm, a film thickness nonuniformity of ±5%, and a number of particles of less than 20 (over 200 nm in diameter) were achieved at a deposition temperature of 680°C for in-situ arsenic-doped poly-Si deposition on a 200-mm-diameter silicon (Si) wafer. Moreover, it was confirmed that the concentration of As in the poly-Si film was low at the initial stage of deposition, and that this process has a high gap filling capability in a hole of 0.18 µm width and 7 µm depth. It was also confirmed that there were conditions for a high step coverage of more than 1. These properties are inferred to be due to the adsorbed AsH3 preventing the adsorption of SiH4.