{TAIL ~ The impurity layer} of high impurity concentration is formed between {HEAD ~ the first semiconductor substrate} and the epitaxial layer 
{ TAIL ~ The impurity layer } of high impurity concentration is formed between { HEAD ~ the first semiconductor substrate } and the epitaxial layer
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH