Evolution of hydrogen induced defects during annealing of plasma treated Czochralski silicon

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Vol. 253; no. 1-2; pp. 176 - 181
• Main Authors: Nordmark, Heidi, Ulyashin, Alexander, Walmsley, John C., Tøtdal, Bård, Holmestad, Randi
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2006
• Subjects: AFM; Hydrogen; Silicon; TEM; Hydrogen; AFM; Silicon; TEM; 61.72.Tt; 61.72.Qq; 61.72.Nn
• ISSN: 0168-583X; 1872-9584
• DOI: 10.1016/j.nimb.2006.10.043

Transmission electron microscopy (TEM) and atomic force microscopy (AFM) are used to study the temperature evolution of hydrogen plasma induced defects in silicon. Hydrogen plasma treated n- and p-doped Czochralski silicon samples were annealed at temperatures between 200 and 1000°C for up to 10h in air. Platelets are formed on {111} and {100} crystallographic planes. The structural defects are similar in n-type and p-type material. Small defects at the surface anneal out at temperatures above 400°C and {111} platelets start to dissolve above 500°C, except in highly p-doped samples where the platelets are stable up to 600°C. The hydrogen penetrates deeper into a low doped than a high doped sample, resulting in platelet formation deeper into the sample. At annealing temperatures above 800°C, an amorphous oxide layer forms at the surface of the sample. New platelets form after 1h annealing at 1000°C. The roughest surface is found in highly n-doped samples, hydrogenated at high plasma frequency for long exposure times. For high annealing temperatures the roughness decreases.