Measurement of the 3He(d, p)4He nuclear reaction cross section by coincidence detection of alphas and protons : Application to the determination ofthe 3He desorption rate from helium bubbles in silicon

The cross section of the 3 He(d,p) 4 He nuclear reaction has been measured with deuteron energies ranging from 347 keV to 992 keV. Both alpha-particles and high-energy protons from the 3 He implanted layer are detected incoincidence to prevent any interference, which can induce some errors in the determination of the cross section. The dispersion of the 3 He(d, p) 4 He reaction cross section was found better than those obtained by other methods. Differential cross section measurements by detecting the protons at 0° and 165° demonstrate an isotropical emission of the nuclear products in the center-of-mass frame at energies below 0.65 MeV. The total cross section represented by a fit function is compared with data from literature. With the described coincidence arrangement, we obtained a reduction by a factor 10 4 of the number of elastically scattered particles. This allows us to enhance the probing depth in silicon to 5.5 μm with a depth resolution close to 0.1 μm.