METHOD OF MANUFACTURING PHOTODIODE, AND PHOTODIODE

• Main Authors: SAKAMOTO AKIRA, NAGANO TERUMASA, YAMAMURA KAZUHISA, FUJII YOSHIMARO
• Format: Patent
• Language: English
• Published: 20.01.2011
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PROBLEM TO BE SOLVED: To provide the method of manufacturing a photodiode which is a silicon photodiode and has sufficient spectral sensitivity characteristics for a near-infrared wavelength band region, and the photodiode.SOLUTION: An ntype semiconductor substrate 1 which has a first principal surface 1a and a second principal surface 1b opposed to each other and on the first principal surface 1a side of which a ptype semiconductor region 3 is formed is prepared. Pulse laser beam is irradiated on a region opposed to the ptype semiconductor region 3 at least in the second principal surface 1b of the ntype semiconductor substrate 1 and an irregular unevenness 10 is formed. After the irregular unevenness 10 is formed, an accumulation layer 11 having higher impurity density than that of the ntype semiconductor substrate 1 is formed on the second principal surface 1b side of the ntype semiconductor substrate 1. After the accumulation layer 11 is formed, the ntype semiconductor substrate 1 is heat treated.