Characterization of a sandwich-type large CVD single crystal diamond particle detector fabricated using a lift-off method

• Published in: Diamond and related materials 2012-04, Vol.24, p.74-77
• Main Authors: Tsubouchi, Nobuteru, Mokuno, Y., Kakimoto, A., Konno, Y., Yamada, H., Chayahara, A., Kaneko, J.H., Fujita, F., Shikata, S.
• Format: Article
• Language: English
• Subjects: Atomic, molecular and charged-particle sources and detectors; Charge; Charged-particle beam sources and detectors; Chemical vapor deposition; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Crystallinity; CVD; Detectors; Exact sciences and technology; Freestanding; Fullerenes and related materials; diamonds, graphite; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Lift-off process; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Micrographs; Physics; Pulse height; Single crystal diamond; Single crystals; Specific materials; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Transits; Ultraviolet
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2011.11.003

Crystallinity of a freestanding large (size: ~9×7mm) undoped single crystal (SC) diamond film grown by plasma chemical vapor deposition (CVD) and radiation response of a sandwich-type radiation detector made from this SC plate to α particles were investigated. The freestanding SC film was formed by elimination of a substrate using a so-called “lift-off method” after the growth of a thick-film on a pre-ion-implanted substrate. The formed SC plate has a high optical transparency, indicating no remarkable optical absorption seen in the wavelength from ultraviolet to near-infrared region. In the energy spectra of 5.486MeV α-particles, relatively sharp peaks were observed for both hole and electron transits. For the hole transit, the peak resolution of the pulse height distribution and charge collection efficiency (CCE) were ~0.7% and 98%, respectively. On the other hand, for the electron transit, the peak resolution and CCE obtained were ~4.4% and 89%, respectively. In the photoluminescence spectrum at room temperature, a strong sharp peak around 235nm corresponding to free exciton and a weak visible band mainly related to nitrogen-vacancy complex were observed. The spectral width of the (004) plane X-ray rocking curve was 16.5″. The micrograph taken using crossed-polarizers demonstrated that there are some white regions and four-petaled patterns, originating from internal strain and most likely threading dislocations, respectively. ► A large undoped freestanding SC diamond plate was produced by the lift-off method. ► The formed SC plate has a high optical transparency. ► In the energy spectra of 5.486MeV α-particles, the peak resolution (FWHM) and CCE were ~0.7 % and 98% for holes. ► The peak resolution and CCE obtained were ~4.4 % and 89% for electrons. ► In the PL spectra at RT, a sharp peak around 235nm and a weak visible band were observed and FWHM of the X-ray rocking curve was 16.5″.