Last week was not a good week for Microsoft CEO Steve Ballmer. After being slammed by Microsoft founder Paul Allen for being “unethical”, at the beginning of the week he finished the week being told that only 40% of Microsoft staff thought he was doing a good job.He also found out that Microsoft’s Windows Phone continues to disappoint and that sales are falling, not climbing as Microsoft had hoped (see separate story).

The company also got slammed after filing an antitrust complaint in Europe against Google. Critics called the move hypocritical, and suggested that it was a sign that Microsoft cannot compete with Google’s search technology.

Even his own employees are having second thoughts about his leadership. When asked “Do you approve of the way your CEO is leading the company?”, only 40 percent of Microsoft employees surveyed said yes, according to Glassdoor.com.

 No. 1 is Google’s outgoing CEO Eric Schmidt, who scored a 96 percent approval rating in the annual tech boss approval survey.

Ballmer’s approval as a boss ranks last among the top dozen tech companies, according to the survey.

Glassdoor.com said Ballmer saw the second biggest drop among CEOs evaluated. Between March 2009 and March 2010, Ballmer’s average approval rating was 46 percent, but has dropped to 40 percent in the past year.

Amazon’s Jeff Bezos had an 83 percent approval rate, down slightly, according to the survey.