Physical and electrical properties of reactive molecular-beam-deposited aluminum nitride in metal-oxide-silicon structures

Ragnarsson, L.-Å.; Bojarczuk, N. A.; Copel, M.; Gusev, Evgeni; Karasinski, J.; Guha, Supratik

doi:10.1063/1.1555687

Cited by 18 publications

(11 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…79 The high mechanical properties 42 of Al 2 O 3 have further enabled its use as a wear-resistant coating in NEM devices, 79 bridge or cantilever in nanomechanical resonator devices, 80 or postfabrication frequency tuning layer for resonant devices. 49,81 AlN was similarly an early high-k candidate to replace SiO 2 in CMOS device applications as both a gate dielectric 82,83 and reaction barrier layer for other oxide high-k dielectrics. 84 It has also been examined as a gate dielectric in III-V devices where particularly close lattice matching exists with GaN.…”

Section: Ecs Journal Of Solid State Science and Technology 6 (10) N1mentioning

confidence: 99%

Review—Investigation and Review of the Thermal, Mechanical, Electrical, Optical, and Structural Properties of Atomic Layer Deposited High-kDielectrics: Beryllium Oxide, Aluminum Oxide, Hafnium Oxide, and Aluminum Nitride

Gaskins

Hopkins

Merrill

et al. 2017

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

Atomic layer deposited (ALD) high-dielectric-constant (high-k) materials have found extensive applications in a variety of electronic, optical, optoelectronic, and photovoltaic devices. While electrical, optical, and interfacial properties have been the primary consideration for such devices, thermal and mechanical properties are becoming an additional key consideration for many new and emerging applications of ALD high-k materials in electromechanical, energy storage, and organic light emitting diode devices. Unfortunately, a clear correspondence between thermal/mechanical and electrical/optical properties in ALD high-k materials has yet to be established, and a detailed comparison to conventional silicon-based dielectrics to facilitate optimal material selection is also lacking. In this regard, we have conducted a comprehensive investigation and review of the thermal, mechanical, electrical, optical, and structural properties for a series of prevalent and emerging ALD high-k materials including aluminum oxide (Al 2 O 3 ), aluminum nitride (AlN), hafnium oxide (HfO 2 ), and beryllium oxide (BeO). For comparison, more established silicon-based dielectrics were also examined, including thermally grown silicon dioxide (SiO 2 ) and plasma-enhanced chemically vapor deposited hydrogenated silicon nitride (SiN:H). We find that in addition to exhibiting high values of dielectric permittivity and electrical resistance that exceed those of SiO 2 and SiN:H, the ALD high-k materials exhibit equally exceptional thermal and mechanical properties with coefficients of thermal expansion ≤ 6 × 10 -6 / • C, thermal conductivites (κ) of 3-15 W/m K, and Young's modulus and hardness values exceeding 200 and 25 GPa, respectively. In many cases, the observed extreme thermal/mechanical properties correlate with the presence of crystallinity in the ALD high-k films. In contrast, some of the electrical and optical properties correlate more strongly with the percentage of ionic vs. covalent bonds present in the high-k film. Overall, the ALD high-k dielectrics investigated concurrently exhibit compelling thermal/mechanical and electrical/optical properties. The drive to reduce gate leakage currents in highly scaled complementary metal-oxide-semiconductor (CMOS) transistors has led to the exploration and development of a wide variety of high-dielectricconstant (high-k) materials to replace silicon dioxide (SiO 2 ) as the insulating gate dielectric material.1-8 Many of these same high-k materials have found additional applications in future non-CMOS logic and memory storage products such as solid-state electrolytes in resistive switching devices, 9,10 tunnel barriers in spin-transport devices, 11 and as a ferroelectric in magnetoelectric devices. While electrical, physical, and thermodynamic properties have clearly been a key consideration in all of the above applications, thermal properties have become an additional important consideration for higk-k dielectrics as aggressive dimensional scaling of devices has created the need to dissipate ...

show abstract

Section: Ecs Journal Of Solid State Science and Technology 6 (10) N1mentioning

confidence: 99%

Review—Investigation and Review of the Thermal, Mechanical, Electrical, Optical, and Structural Properties of Atomic Layer Deposited High-kDielectrics: Beryllium Oxide, Aluminum Oxide, Hafnium Oxide, and Aluminum Nitride

Gaskins

Hopkins

Merrill

et al. 2017

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…The dielectric permittivity was calculated to be 6.1-7. Others have studied AlN by molecular beam deposition on silicon wafers with a HF-last preclean and found a much higher dielectric permittivity of 18 [6]. This work compared interface degradation for AlN deposited on SiO 2 or Al 2 O 3 with AlN deposited directly on Si.…”

Section: Contents Lists Available At Sciencedirectmentioning

confidence: 94%

Electrical and materials properties of AlN/ HfO2 high-k stack with a metal gate

et al. 2009

View full text Add to dashboard Cite

“…The IBM group recently reported that a reactive atomic beam grown AlN film also has a high density of sheet positive fixed charge ( ϳ 5 ϫ 10 12 cm Ϫ2 ). 21 Therefore, the incorporation of a proper amount of N into the Al 2 O 3 , as in thermal nitridation, successfully nullified the V FB shift.…”

Section: Resultsmentioning

confidence: 96%

“…AlN is drawing great interest as a gate dielectric in the major semiconductor industry. 21 However, the AlN films were grown by the reactive-atomic-beam deposition technique, 21 which is believed to be less appropriate as a mass-production compatible high-k deposition technique compared to ALD. Therefore, the optimized nitridation process of ALD Al 2 O 3 films was investigated because the ALD and nitridation processes are easily adaptable to the semiconductor fabrication processes.…”

mentioning

confidence: 99%

Optimized Nitridation of Al[sub 2]O[sub 3] Interlayers for Atomic-Layer-Deposited HfO[sub 2] Gate Dielectric Films

Park

Cho

Park

et al. 2004

Electrochem. Solid-State Lett.

View full text Add to dashboard Cite

HfO 2 /Al 2 O 3 gate dielectric thin-film stacks were atomic-layer-deposited on HF-cleaned Si wafers. The 2.3 nm thick Al 2 O 3 interlayer was treated under an NH 3 atmosphere at 790°C for 40 s with and without rf plasma prior to a 4 nm thick HfO 2 film deposition. Plasma nitridation increased Al 2 O 3 interlayer thickness by 0.9 nm and decreased overall capacitance, whereas thermal nitridation did not, and overall capacitance was the same as that of a nontreated HfO 2 /Al 2 O 3 stack. The thermal stability of the capacitance density and flatband behavior were also improved by thermal nitridation of the interlayer. Furthermore, nitridation of the Al 2 O 3 interlayer greatly reduced the interface trap density of the samples.As complementary metal oxide semiconductor field-effect transistor ͑CMOSFET͒ device scaling reaches the sub-0.1 m era, high dielectric ͑high-k͒ HfO 2 thin films are attracting increasing interest as a replacement for nitrided SiO 2 gate oxide films. 1-4 Physically thicker high-k HfO 2 films can greatly suppress the gate leakage current (I gate ) while maintaining a high gate capacitance specifically when it is in the amorphous state. A high gate capacitance is essential to minimizing the short-channel effect and to maximizing the drain saturation current as well as to achieving a high channelcontrollability of the gate.The atomic layer deposition ͑ALD͒ process appears to be a most suitable method for high-k film growth due to its excellent process controllability even for extremely thin ͑Ͻ5 nm͒ high-k films. 5,6 However, most vapor-phase grown HfO 2 thin films appear to have interfacial layers ͑IL͒ at the Si interface due to the presence of excess oxidizing elements, and simultaneous Si diffusion into the growing films. 7,8 This reduces the overall capacitance density, which must be minimized to achieve high-k characteristics. The other serious drawback of high-k gate oxides compared to SiO 2 is the high interfacial fixed-charge density (Q f ) 9,10 and the high interface trap density (D it ). 2,11 In terms of the device operation of the CMOSFET, the dopant penetration from the doped polysilicon gate to the channel area ͑specifically B in p-type MOSFET͒ is another serious problem to be solved. 12 There are several reports showing that N incorporation into high-k gate dielectric reduced B penetration and improved the thermal stability of the capacitance density. 13-15 The author's own study found that the adoption of an Al-containing amorphous interlayer is a good method for suppressing As penetration at temperatures as high as 1000°C. 16 However, it has been reported that the Al 2 O 3 /SiO 2 or Al 2 O 3 /Si interface has a high density of negative fixed charges ͑Ͼ5 ϫ 10 12 cm Ϫ 2 ), which induces a positive flatband voltage (V FB ) shift. 17-19 Furthermore, the Al 2 O 3 interlayer on its own is not a good reaction barrier layer so it cannot successfully suppress Si diffusion into the high-k layer and O diffusion to the film/Si interface. Therefore, there was marginal improvement in the thermal s...

show abstract

Physical and electrical properties of reactive molecular-beam-deposited aluminum nitride in metal-oxide-silicon structures

Cited by 18 publications

References 24 publications

Review—Investigation and Review of the Thermal, Mechanical, Electrical, Optical, and Structural Properties of Atomic Layer Deposited High-kDielectrics: Beryllium Oxide, Aluminum Oxide, Hafnium Oxide, and Aluminum Nitride

Review—Investigation and Review of the Thermal, Mechanical, Electrical, Optical, and Structural Properties of Atomic Layer Deposited High-kDielectrics: Beryllium Oxide, Aluminum Oxide, Hafnium Oxide, and Aluminum Nitride

Electrical and materials properties of AlN/ HfO2 high-k stack with a metal gate

Optimized Nitridation of Al[sub 2]O[sub 3] Interlayers for Atomic-Layer-Deposited HfO[sub 2] Gate Dielectric Films

Contact Info

Product

Resources

About