Ge(Sn) growth on Si(001) by magnetron sputtering

Abstract

The semi-conductor Ge 1x Sn x exhibits interesting properties for optoelectronic applications. In particular, Ge 1x Sn x alloys with x  0.1 exhibit a direct band-gap, and integrated in complementary-metal-oxide-semiconductor (CMOS) technology, should allow the development of Si photonics. CMOS-compatible magnetron sputtering deposition was shown to produce monocrystalline Ge 1x Sn x films with good electrical properties at low cost. However, these layers were grown at low temperature (< 430 K) and contained less than 6% of Sn. In this work, Ge 1x Sn x thin films were elaborated at higher temperature (> 600 K) on Si(001) by magnetron sputtering in order to produce low-cost and CMOS-compatible relaxed pseudocoherent layers with x ≥ 0.1 exhibiting a better crystallinity. Ge 1x Sn x crystallization and Ge 1x Sn x crystal growth were investigated. Crystallization of an amorphous Ge 1x Sn x layer deposited on Si(001) or Ge(001) grown on Si(001) leads to the growth of polycrystalline films. Furthermore, the competition between Ge/Sn phase separation and Ge 1x Sn x growth prevents the formation of large-grain Sn-rich Ge 1x Sn x layers without the formation of -Sn islands on the layer surface, due to significant atomic redistribution kinetics at the crystallization temperature (T = 733 K for x = 0.17). However, the growth at T = 633 K of a highly-relaxed pseudo-coherent Ge 0.9 Sn 0.1 film with low impurity concentrations (< 2 × 10 19 at cm 3 ) and an electrical resistivity four orders of 2 magnitude smaller than undoped Ge is demonstrated. Consequently, magnetron sputtering appears as an interesting technique for the integration of optoelectronic and photonic devices based on Ge 1x Sn x layers in the CMOS technology.

Morphology and structure evolution of multilayered Ge/Si quantum dots grown by magnetron sputtering

“…In recent years, fruitful research [11][12][13][14] of fabricating QDs by magnetron sputtering have negated the preexisting preconception that the high kinetic energy of particles and the high deposition rate of magnetron ion beam sputtering might induce drastic growth that leads to the formation of polycrystalline islands and the inhibition of the formation of self assembled QDs. Magnetron sputtering is gradually developing into an emerging QD growth technique even though its relevant literatures are still few, and the corresponding obtained evolution mechanism of QDs are still focused on the single-layer structure.…”

“…In recent years, fruitful research [13][14][15][16] of fabricating QDs by magnetron sputtering have negated the preexisting preconception that the high kinetic energy of particles and the high deposition rate of magnetron ion beam sputtering might induce drastic growth that leads to the formation of polycrystalline islands and the inhibition of the formation of self-assembled QDs. The latest typical work on the growth of multilayer Ge/Si structures by magnetron sputtering was carried out by Peng et al [16], which involved the study of boron-doped Si 1-x Ge x films with multilayer structure of five periods, the work focused on the effects of post annealing on the structure of the samples and the influence of doped atoms on the thermoelectric properties of the samples.…”

“…In recent years, fruitful research [13–16] of fabricating QDs by magnetron sputtering have negated the preexisting preconception that the high kinetic energy of particles and the high deposition rate of magnetron ion beam sputtering might induce drastic growth that leads to the formation of polycrystalline islands and the inhibition of the formation of self‐assembled QDs. The latest typical work on the growth of multilayer Ge/Si structures by magnetron sputtering was carried out by Peng et al.…”

Study on crystal growth of Ge/Si quantum dots at different Ge deposition by using magnetron sputtering technique

“…Samavati et al 25 studied the effects of various parameters of RF magnetron sputtering, including substrate temperature, deposition time, Ar flow rate, RF power, working pressure, annealing temperature, and annealing time, on the structure and properties of Si-based Ge quantum dots (Ge/Si QDs). Khelidj et al used magnetron sputtering to grow Ge 1− x Sn x films with potential for CMOS (complementary-metal-oxide-semiconductor) applications and analyzed the nanostructure and electrical properties of the Ge–Sn alloys in these films 26 . In addition, the work on the formation of multi-layer Ge QDs in Ge/SiO 2 or Ge/Si bi-layers with multiple repetition periods grown by magnetron sputtering has also been reported 27 , 28 .…”

Impact of strain engineering and Sn content on GeSn heterostructured nanomaterials for nanoelectronics and photonic devices

“…Then, they annealed the prepared samples at temperature in the range from 423 to 853 K. They obtained 11% Sn content in the GeSn compound at the beginning of the annealing and then reduced to 4% by raising the temperature. 62 Wei Dou et al used plasma-enhanced chemical vapor deposition technique with different growth temperatures to grow the GeSn alloy. The GeH 4 and SnCl 4 precursors were inserted in the chamber with argon gas between the cathode and anode (see Fig.…”