Activation of boron and recrystallization in Ge preamorphization implant structure of ultra shallow junctions by microwave annealing

An overview is given on the status of n‐type dopant activation and diffusion in Ge, based on a standard ion implantation and annealing scheme. Emphasis is on defect engineering approaches to optimize either or both parameters. A detailed discussion is given on the use of co‐implantation by neutral or other n‐type dopants. As a case study, the impact of the C ion implantation energy and dose on n‐type junctions in p‐Ge by P + C co‐implantation will be given. It is demonstrated that for fixed P implant conditions, there exist an optimum energy and dose for achieving a minimum junction depth by the formation of C–PV complexes. An alternative approach is the use of self‐interstitial management at the end‐of‐range of the P implantation. Finally, an overview is given of alternatives for obtaining shallow, highly activated n‐type junctions in Ge. They rely on: non‐standard implantation schemes, ultra‐short annealing methods or relying on in situ doped epitaxial deposition.

show abstract

“…Quite recently, microwave annealing has been applied to dopant implanted Ge . An example is shown in Fig.…”

Section: Alternative Implantation Annealing and Doping Schemesmentioning

confidence: 99%

Defect engineering for shallow n‐type junctions in germanium: Facts and fiction

Simoen

Schaekers

Liu

et al. 2016

Physica Status Solidi (a)

View full text Add to dashboard Cite

show abstract

“…9) Nevertheless, a primary concern with high-k/metal gate (HKMG) electrodes is their thermal instability, which can lead to band gap shifts, increased equivalent oxide thickness (EOT), uncontrollable threshold voltage, and leakage current. [10][11][12][13] The growth of many monolayers of Si-O or Si-N containing materials at the channel interface is considered desirable for improving the high-k/Si interface quality because these layers could provide the essential, high-quality nature of the SiO 2 /Si interface. To boost the high-k/Si interface efficiency, the proper annealing conditions are essential.…”

Section: Introductionmentioning

confidence: 99%

Study on dopant activation and EOT impact in HKMG stacks using microwave annealing with different frequencies

Divya,

Chen,

Lee

et al. 2024

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

We have examined the dopant activation levels of various materials(Si, SiGe & Ge) annealed at two different frequency i.e., 2.45GHz and 5.8GHz microwave annealing (MWA) with the aim of identifying a material-targeted annealing method that will minimize the annealing process of high thermal budget. Furthermore, we also fabricated high-k/metal gate MOSCAP structure annealed at 2.45GHz and 5.8GHz MWA as the post-metallization annealing process. The results show that microwave annealing at 2.45GHz is more efficient than high frequency 5.8GHz MWA at 3000W in minimizing the interface trapped charged and the reduction in leakage current density. However, there is slight clear reduction in capacitance as the frequency increased to 5.8GHz resulting in increase of interfacial layer thickness. Due to undesirable effects such as Al diffusion into the dielectric layer, microwave annealing at 2.45GHz demonstrates great a potential candidate as a post-metallization annealing method for high-k/metal gate structures.

show abstract

“…However, ion implantation damages the Ge crystal [11,12]. This creates the need for a high temperature treatment to anneal out the defects and recrystallize Ge [13][14][15][16]. A high heating rate can induce structural damage while a low annealing time might not fully crystallize the implanted region, resulting in defect formation that will affect the junction leakage current [17].…”

Section: Introductionmentioning

confidence: 99%

Selective Epitaxial Growth of In Situ Doped SiGe on Bulk Ge for p+/n Junction Formation

et al. 2020

View full text Add to dashboard Cite

Epitaxial in situ doped Si0.73Ge0.27 alloys were grown selectively on patterned bulk Ge and bulk Si wafers. Si0.73Ge0.27 layers with a surface roughness of less than 3 nm were demonstrated. Selectively grown p+Si0.73Ge0.27 layers exhibited a resistivity of 3.5 mΩcm at a dopant concentration of 2.5 × 1019 boron atoms/cm3. P+/n diodes were fabricated by selectively growing p+- Si0.73Ge0.27 on n-doped bulk Ge and n-doped Si wafers, respectively. The geometrical leakage current contribution shifts from the perimeter to the bulk as the diode sizes increase. Extracted near midgap activation energies are similar to p+/n Ge junctions formed by ion implantation. This indicates that the reverse leakage current in p+/n Ge diodes fabricated with various doping methods, could originate from the same trap-assisted mechanism. Working p+/n diodes on Ge bulk substrates displayed a reverse current density as low as 2.2·10−2 A/cm2 which was found to be comparable to other literature data. The layers developed in this work can be used as an alternative method to form p+/n junctions on Ge substrates, showing comparable junction leakage results to ion implantation approaches.

show abstract

Activation of boron and recrystallization in Ge preamorphization implant structure of ultra shallow junctions by microwave annealing

Cited by 11 publications

References 22 publications

Defect engineering for shallow n‐type junctions in germanium: Facts and fiction

Defect engineering for shallow n‐type junctions in germanium: Facts and fiction

Study on dopant activation and EOT impact in HKMG stacks using microwave annealing with different frequencies

Selective Epitaxial Growth of In Situ Doped SiGe on Bulk Ge for p+/n Junction Formation

Contact Info

Product

Resources

About