Wafer bowing control of free-standing heteroepitaxial diamond (100) films grown on Ir(100) substrates via patterned nucleation growth

Highlights

•

Wafer bowing control of free-standing heteroepitaxial diamond (100) films

•

Effect of patterned nucleation and growth (PNG) technique on wafer bowing reduction

•

Influence of nucleation region patterns of PNG on wafer bowing

•

Internal stress analysis of PNG films via confocal micro-Raman spectroscopy

---

Abstract

The potential of patterned nucleation growth (PNG) technique to control the wafer bowing of free-standing heteroepitaxial diamond films was investigated. The heteroepitaxial diamond (100) films were grown on an Ir(100) substrate via PNG technique with different patterns of nucleation regions (NRs), which were dot-arrays with 8 or 13 μm pitch aligned to < 100 > or < 110 > direction of the Ir(100) substrate. The wafer bows and the local stress distributions of the free-standing films were measured using a confocal micro-Raman spectrometer. For each NR pattern, the stress evolutions within the early stage of diamond growth were also studied together with a scanning electron microscopic observation of the coalescing diamond particles. These investigations revealed that the NR pattern, in terms of pitch and direction of dot-array, strongly affects the compressive stress on the nucleation side of the diamond film and dominantly contributes to the elastic deformation of the free-standing film. This indicates that the PNG technique with an appropriate NR pattern is a promising solution to fabricate free-standing heteroepitaxial diamond films with extremely small bows.

Abbreviations

• PNG, patterned nucleation growth; 
• NR, nucleation region; 
• CVD, chemical vapor deposition; 
• FWHM, full width at half maximum; 
• TEC, thermal expansion coefficient;
• RT, room temperature

Keywords

• Heteroepitaxial diamond; 
• Chemical vapor deposition; 
• Free-standing film; 
• Patterned nucleation growth; 
• Micro-Raman spectroscopy
• • • 
      
      SOURCE:SCIENCEDIRECT
    • • If you need more information about substrate wafer, please visit our website:http://www.qualitymaterial.net , send us email at powerwaymaterial@gmail.com.