* Holding above 25-day moving average at 9,600 seen key
* Trend-following funds buy stock futures
* Semiconductor wafer shares up after report of higher prices
TOKYO, July 22 (Reuters) - Japan's Nikkei stock average rose 0.8 percent on Wednesday as technical buying boosted futures prices, but gains were capped as exporters such as Canon Inc were shaky due to the yen's firmness.
Chipmakers including Shin-Etsu Chemical jumped after the Nikkei business daily said its unit Shin-Etsu Handotai is in talks to raise the price of 300 mm semiconductor wafers by 30-40 percent.
The benchmark Nikkei spent much of the morning in negative territory, but falls were countered by growing optimism about a recovery in the U.S. economy after a spate of strong earnings reports.
Analysts said one key technical level for the Nikkei was 9,600, just under where the 25-day moving average comes in, and that the index holding above that level prompted some trend-following funds to buy stock futures.
"The market received a boost as futures players bought back short positions," said Takahiko Murai, general manager of equities at Nozomi Securities.
"But activity in the cash market stayed subdued, with investors worried about exporters' profits as the yen remains strong."
The benchmark Nikkei gained 73.50 points to 9,725.52 after closing at a two-week high on Tuesday. The broader Topix advanced 0.6 percent to 907.08.
The yen rose against other major currencies on Wednesday after remarks by Federal Reserve Chairman Ben Bernanke offered a cautious view on the U.S. economy, reducing investor risk appetite.
Shin-Etsu Chemical climbed 5.5 percent to 4,770 yen, while rival Sumco Corp gained 4.8 percent to 1,582 yen.
Defensive shares also helped the Nikkei rise. Seasoning maker Ajinomoto was up 4.2 percent at 827 yen.
Sapporo Holdings rose 3 percent to 555 yen after the Nikkei business daily reported on Wednesday that the brewer apparently broke even in January-June, beating the company's own forecast for an operating loss of 2 billion yen ($21.4 million).
Sony Corp dipped 0.2 percent to 2,310 yen and Canon fell 1.3 percent to 3,160 yen. (Reporting by Rika Otsuka; Editing by Joseph Radford)