The conclusions come from a survey of 1,795 men and women at seven local high-technology companies, conducted by the Anita Borg Institute for Women and Technology in Palo Alto and the Clayman Institute for Gender Research at Stanford University.
Despite possessing technical expertise on par with top men, the senior technical women were more likely to be in management rather than "individual contributor" roles that often set the fundamental technology agendas for their companies.
They were more likely than their male peers to view themselves as "assertive," but less likely to consider themselves entrepreneurial or innovative.
At just 4 percent of the sample, senior technical women represent a rarity in the technology industry.
Researchers combed the data for clues as to how these high achievers had forged their paths to success in the male-dominated tech world.
"In this report we asked, 'What about the women who have made it, who beat the odds? What can they tell us about what it takes to achieve these positions?'" according to social scientist Caroline Simard, a co-author of the study and research director for the Anita Borg Institute.
The institute was launched in 1997 by local computer scientist Anita Borg, who named it the Institute for Women and Technology. It was re-named for Borg after she died of brain cancer in 2003 at the age of 54.
Borg believed women should "assume their rightful place at the table" in actively driving the conception and development of life-defining technologies.
The institute is supported by corporate "partners," including major tech companies such as Google, HP, Microsoft, Intel, Yahoo and Cisco.
Simard said the research was designed to answer companies' questions about the best policies for recruiting, retaining and advancing technical women.
"They (the companies) come to us and say, 'We want to get more insight about what's happening with our technical women and how we can support them in advancing their careers,'" she said. She declined to specifically name the seven high-technology companies in Silicon Valley from which the data was gathered in 2008.
Women and men at senior technical levels largely agreed when asked to identify "attributes for successful people in technology."
Those were listed, in order of importance, as analytical, innovative, questioning, risk-taking, collaborative, entrepreneurial and assertive.
Senior tech women and men viewed themselves in similar numbers as analytical, questioning, risk-taking and collaborative.
Nearly 56 percent of senior women saw themselves as "assertive," while only 48.4 percent of senior men considered themselves so.
One mid-level woman said assertiveness is necessary for female success in the male-dominated engineering culture, even if it does not come naturally.
"There are certain behaviors that are required of women in technology because of the behaviors that male engineers display," said one survey participant, a mid-level technical woman.
"There's a way of communicating where male engineers communicate in such a way that it sounds like they know what they're talking about and they are right. And you know, sometimes it comes across as arrogant and annoying, but it's effective.
"And I think that often women don't learn to do that in technical careers. They never sort of advance up the technical ladder."
Simard also noted that the propensity for assertiveness varies along cultural dimensions.
A senior woman described how she had to change her style to fit the North American technical culture.
"I was raised to not be aggressive, be very modest, don't toot your own horn.
"I think in America you need to be a little more assertive. You often have to sell yourself, promote yourself. Let people know what you've done, what you're capable of doing."
Another senior technical woman said self-promotion had been necessary for success.
"I've had to ask for it," she said.
"If I was just complacent and I just did my work ... I wouldn't be where I am. I've had to be very aggressive and basically say, 'Hey, I'm ready for a promotion. Let's sit down and talk about this. I should be at a higher level.'"
While 60.2 percent of senior technical men described themselves as "innovators," only 38.1 percent of top technical women saw themselves that way.
"A loss of diverse ideas in the innovation process represents lost business opportunities for companies," Simard said.
Many tech companies categorize positions in terms of whether they are "individual contributors" or managers. This dual-ladder career structure was widely adopted in the 1950s by firms heavily dependent on scientific talent.
It was a way to provide advancement opportunities for high-performing technical employees who did not have managerial aspirations.
Simard said it is a matter of concern that top women are more likely to be in management rather than "individual contributor" roles because the "ICs" have greater opportunities to achieve deep technical specialization, set technical directions for company products and be involved in patenting and publishing activities.
"At a certain level (in our company), you have to choose whether you will be an engineer or a manager," said a mid-level technical man. "And I cannot name you a single female (top level) technical leader that I know of at this company."
A mid-level technical woman said, "(At the highest level) we don't have women technical Fellows or anything like that, we have women VPs.
"Fellow is the equivalent of 'technical god.' There are no women. Then there are (top level engineers) one step lower, and I think that one is a woman. It makes me so mad."
In the area of work-life balance, the survey found that nearly a quarter of senior technical women rely on a spouse who has primary responsibility for the household.
However, senior women are more than twice as likely as senior men to have a partner who works full-time.
Senior women are significantly more likely than senior men to report that they delayed having children and cut back on their social lives to achieve their career goals.