Enhancement efficiency of UMSM photodetectors by doping AP and IPA in TMAH solutions for fabrication process

Jarnpen, Thikhamphorn; Sutticharoen, Kamonwan; Niemcharoen, Surasak

Enhancement efficiency of UMSM photodetectors by doping AP and IPA in TMAH solutions for fabrication process

Author(s)

Jarnpen, Thikhamphorn

Sutticharoen, Kamonwan

Niemcharoen, Surasak

Date Issued

January 1, 2018

Type

Conference Paper

Abstract

This paper presents electrical characteristics and finds the conditions in UMSM photodetectors fabrication by chemical wet etching process. Isopropyl alcohol (IPA) and ammonium peroxodisulfate (AP) technique was doped into tetramethyl ammonium hydroxide (TMAH) solutions. Using n-type silicon wafers these have resistivity as 5-10 ohm-cm. It was found that doping 7 gm/l AP with 5wt% TMAH, surface of silicon was etched smoother than adding 30 %vol IPA into 25 wt% TMAH solutions approximately 5 times. Then measure the electrical characteristics of UMSM photodetectors to determine dark current and photocurrent. UMSM photodetectors was fabricated by 5%wt TMAH solutions 7 gm/l AP added technique with leakage current and photocurrent are 7 µA and 57.7 µA, respectively. And UMSM photodetectors was fabricated by 25 %wt TMAH solutions 30 %vol IPA added technique with dark current and photocurrent are 8.9 µA and 46.1 µA, respectively. According to this study found that TMAH solutions with AP added is suitable for design photodetector in further research.

Citation

Lecture Notes in Engineering and Computer Science, 2, 2018