成果報告書詳細
管理番号20150000000601
タイトル*平成26年度中間年報 SIP(戦略的イノベーション創造プログラム) 次世代パワーエレクトロニクス 将来のパワーエレクトロニクスを支える基盤研究開発 ダイヤモンドパワーデバイス用ウエハの研究開発
公開日2015/8/4
報告書年度2014 - 2014
委託先名独立行政法人産業技術総合研究所 国立大学法人千葉大学 国立大学法人大阪大学
プロジェクト番号P14029
部署名電子・材料・ナノテクノロジー部
和文要約
英文要約Title: Cross-ministerial Strategic Innovation Promotion Program / Next Generation Power Electronics / Fundamental Research and Development Project for Future Power Electronics / Development of Diamond Wafer for Diamond Power Plectronic Device (FY2014-FY2015) FY2014 Annual Report

1. Development of low defect single crystal diamond wafer of 2inch
Development of large and low defect diamond wafer is important for realizing future diamond power electric devices. The main purpose of this feasibility study is to extract technical issues which limiting the growth of large bulk diamond crystal by chemical vapor deposition. In this fiscal year, fabrication of low dislocation density diamond wafers by direct wafer fabrication technology was tested. As a result, a wafer (7×6mm2) with very low dislocation density was successfully fabricated. Also, pulse microwave power source has been introduced to a microwave plasma CVD reactor. In the preliminary experiments, we confirmed that pulse plasma with reasonable power density was successfully generated as planned.

2. Wafer machining
2-1. Laser machining
Feasibility study for diamond wafer machining such as dicing, slicing, chamfering and planarization of diamond wafer by laser machining was conducted.
Firstly, “Dicing” process is studies using a forth harmonic wave of Nd: YVO4 laser was focused on the diamond with a convex lens. Maximum removal widths were ~40 μm at the entrance of the grooves in two cases, varying the scanning conditions. The fine groove is observed without any clear defects such as cracking and peeling on the cut surface. In addition, deep cutting was tested for slicing; as a result, the depth of about 3mm was achieved.

2-2. Planarization of wafer
In order to reduce the defects in the CVD grown layer, it is necessary to smooth the growth surface of the substrate without any damages. We developed a sacrificial layer etching and chemical mechanical polishing as surface smoothing method. RF etching apparatus was established for performing a sacrificial glass layer etching experiments. By adjusting the mixing ratio of etching gas, we can make the etching rate of the glass and diamond completely equal, which indicate that it is possible to obtain flattened wafer by this fabrication process.

3. Theoretical study on diamond power device
This research theme clarifies the applicability of diamond to a high voltage and large current power switching device. This year, we discussed about the method to clarify the merit and demerit of diamond semiconductor material to use in power switching device. Also, the basic property of the diamond power device is discussed. One good example of diamond power device is a line switch or circuit breaker to use in high voltage power distribution system. And, we did preliminary calculation of power and energy loss with comparing conventional Si device switch. The results indicate that the high voltage unipolar device with utilizing diamond semiconductor gives lower power and energy loss than conventional bipolar type Si bipolar device. The temperature characteristics of diamond Schottky Barrier Diode (SBD) is also evaluated.
ダウンロード成果報告書データベース(ユーザ登録必須)から、ダウンロードしてください。

▲トップに戻る