INSPECTION DEVICE, INSPECTION METHOD, ELECTROMAGNETIC WAVE INFORMATION PROCESSING DEVICE, ELECTROMAGNETIC WAVE INFORMATION PROCESSING METHOD, AND PROGRAM

• Main Authors: ITO AKIRA, WATABE HEIJI, HOSOI TAKUJI, SHIMURA TAKAYOSHI, NISHIMURA TATSUHIKO, NAKANISHI HIDETOSHI
• Format: Patent
• Language: English; Japanese
• Published: 24.09.2020
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; SEMICONDUCTOR DEVICES; TESTING

To highly accurately evaluate characteristics of a surface layer part in the vicinity of an interface between a semiconductor layer and an insulator layer.SOLUTION: An inspection device comprises: an application part; an irradiation part; a detection part; and a recognition part. The application part applies a plurality of voltages respectively between a semiconductor layer in a semiconductor sample and a reverse side portion of the semiconductor layer out of an insulator layer. The irradiation part irradiates the semiconductor sample with pulse light of a prescribed wavelength region. The detection part detects temporal changes in intensity of a plurality of terahertz waves radiated according to irradiation of the pulse light from the semiconductor sample to which each of the voltages is applied. With the temporal changes of the intensity of the plurality of terahertz waves detected by the detection part for the plurality of voltages, as a target, the recognition part recognizes the temporal changes in intensity of the terahertz waves having the maximal occupancy rate of a component of the terahertz waves radiated according to a transient current caused by a speed difference in diffusion of electrons and positive holes generated by optical excitation in accordance with the irradiation of the pulse light in the semiconductor layer, on the basis of a relationship between a numerical value related to the intensity of a prescribed peak of the terahertz waves and the plurality of voltages.SELECTED DRAWING: Figure 3 【課題】半導体層の絶縁層との界面の近傍の表層部における特性を高精度に評価する。【解決手段】検査装置は、印加部と照射部と検出部と認識部とを備える。印加部は、半導体試料における半導体層と絶縁層のうちの半導体層の逆側の部分との間に複数の電圧をそれぞれ印加する。照射部は、半導体試料に所定の波長領域のパルス光を照射する。検出部は、各電圧が印加されている半導体試料からパルス光の照射に応じて放射されるテラヘルツ波の強度の時間変化を検出する。認識部は、複数の電圧について検出部で検出された複数のテラヘルツ波の強度の時間変化を対象として、テラヘルツ波の所定のピークの強度に係る数値と複数の電圧との関係に基づき、半導体層においてパルス光の照射に応じた光励起で生じる電子および正孔の拡散における速度差による過渡電流に応じて放射されるテラヘルツ波の成分の占有割合が最大であるテラヘルツ波の強度の時間変化を認識する。【選択図】図３