Reduction of Copper Oxide Film to Elemental Copper

Soininen, P.; Elers, Kai‐Erik; Saanila, Ville; Kaipio, S.; Sajavaara, Timo; Haukka, Suvi

doi:10.1149/1.1839491

Cited by 63 publications

(34 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To reduce the copper oxide films to metallic copper after ALD, the samples were heat-treated in vapors of formic acid, based on earlier experience using this reducing agent during copper MOCVD [4] and considering the successful application of organic reducing agents for the reduction of copper oxide [5]. The reduction processes were carried out in-situ after ALD in the same chamber, whereby the formic acid vapor was generated by bubbling or liquid delivery.…”

Section: Methodsmentioning

confidence: 99%

ALD-grown seed layers for electrochemical copper deposition integrated with different diffusion barrier systems

Waechtler

Shihua

Hofmann

et al. 2011

Microelectronic Engineering

View full text Add to dashboard Cite

The deposition of Cu seed layers for electrochemical Cu deposition (ECD) via atomic layer deposition (ALD) of copper oxide and subsequent thermal reduction at temperatures between 110 and 120°C was studied on different diffusion barrier systems. While optimization of the process is required on TaN with respect to reduction and plating, promising results were obtained on blanket PVD Ru. The plating results on layers of ALD Cu with underlying Ru even outperformed the ones achieved on PVD Cu seed layers with respect to morphology and resistivity. Applying the processes to via and line patterns gave similar results, suggesting that a combination of ALD Cu with PVD or ALD-grown Ru could significantly improve the ECD Cu growth.

show abstract

Section: Methodsmentioning

confidence: 99%

ALD-grown seed layers for electrochemical copper deposition integrated with different diffusion barrier systems

Waechtler

Shihua

Hofmann

et al. 2011

Microelectronic Engineering

View full text Add to dashboard Cite

show abstract

“…Figure 13 illustrates the photodegradation phenomena of PVP by light irradiation. 26 Both alcohol and acid reduction mechanisms have been known for decades as generic routes for synthesis by metal oxide reduction, 9,[27][28][29] and Eqs. (4-9) describe the favorable thermodynamics of these reactions.…”

Section: Reactive Sintering Mechanism Of Copper Nanoparticles Using Iplmentioning

confidence: 99%

Reactive Sintering of Copper Nanoparticles Using Intense Pulsed Light for Printed Electronics

Ryu

Kim

Hahn

2010

Journal of Elec Materi

244

126

View full text Add to dashboard Cite

Most commercial copper nanoparticles are covered with an oxide shell and cannot be sintered into conducting lines/films by conventional thermal sintering. To address this issue, past efforts have utilized complex reduction schemes and sophisticated chambers to prevent oxidation, thereby rendering the process cost ineffective. To alleviate these problems, we demonstrate a reactive sintering process using intense pulsed light (IPL) in the present study. The IPL process successfully removed the oxide shells of copper nanoparticles, leaving a conductive, pure copper film in a short period of time (2 ms) under ambient conditions. The in situ copper oxide reduction mechanism was studied using several different experiments and analyses. We observed instant copper oxide reduction and sintering through poly(N-vinylpyrrolidone) functionalization of copper nanoparticles, followed by IPL irradiation. This phenomenon may be explained by oxide reduction either via an intermediate acid created by ultraviolet (UV) light irradiation or by hydroxyl (-OH) end groups, which act like long-chain alcohol reductants.

show abstract

“…8 When Cu wafers with surface oxide layer are annealed in forming gas, hydrogen can act as a reducing agent to convert the surface oxide back to elemental Cu. These reactions are exothermic and can be described by the following: 9,10 CuO ϩ H 2 → Cu ϩ H 2 O (∆H ϭ Ϫ87.1 kJ/mol at 650 K) (1)…”

Section: Resultsmentioning

confidence: 99%

The effect of forming gas anneal on the oxygen content in bonded copper layer

Tan

Chen

Fan

et al. 2005

Journal of Elec Materi

View full text Add to dashboard Cite

Using a combination of copper (Cu) thermocompression bonding and silicon wafer thinning, a face-to-face silicon bi-layer layer stack is fabricated. The oxygen content in the bonded Cu layer is analyzed using secondary ion mass spectrometry (SIMS). Copper-covered wafers that are exposed to the air for 12 h and 12 days prior to bonding exhibit 0.08 at.% and 2.96 at.% of oxygen, respectively. However, prebonding forming gas anneal at 150°C for 15 min on 12-day-old Cu wafers successfully reduces the oxygen content in the bonded Cu layer to 0.52 at.%.

show abstract

Reduction of Copper Oxide Film to Elemental Copper

Cited by 63 publications

References 9 publications

ALD-grown seed layers for electrochemical copper deposition integrated with different diffusion barrier systems

ALD-grown seed layers for electrochemical copper deposition integrated with different diffusion barrier systems

Reactive Sintering of Copper Nanoparticles Using Intense Pulsed Light for Printed Electronics

The effect of forming gas anneal on the oxygen content in bonded copper layer

Contact Info

Product

Resources

About