Shane Todd should have been "stress-free" from work when he sought help from a psychiatrist for depression in April 2012, the head of the Singapore Institute of Microelectronics (IME) told the court on Monday.

This was because he had already told his superiors that he intended to resign in March, said Dr Dim-Lee Kwong, the executive director of the IME. This resignation request was also prior to the one face-to-face meeting that the American researcher had with Huawei executives in April. Dr Todd helped to prepare a proposal for a potential Huawei-IME collaboration, but the project did not get the green light due to "technological" differences between the parties, said Dr Kwong.

The IME head also told the coroner's inquiry into Dr Todd's death that Dr Todd had volunteered to transfer from his area of expertise to the then newly formed Gallium Nitride research group at IME - even though he had no expertise in the area.

While Dr Todd's family has claimed that he feared a machine purchased by the IME would be used for military purposes against export licensing rules, Dr Kwong told the inquiry that he had in fact volunteered to buy the machine as well as go to the United States to be trained in its use.

Dr Todd's father had alleged that his son was left alone in a room to copy a secret recipe for the machine during his 10-day training stint there in early 2012. Dr Kwong said this was unlikely as Veeco had "no proven recipes" beyond the demonstration one they provided with every machine purchase.

Just before lunch, a StarHub representative took the stand and testified that alleged data transfers from Dr Todd's handphone from June 25 to June 29 last year - after it was seized by the police following his death - were possibly the result of background app traffic that occurred without human intervention.

However, the representative was unable to be sure as the logs have been deleted. StarHub keeps data logs for only three months. Dr Todd was found dead in his apartment near Chinatown last June. His parents believe he was murdered.

The investigation officer who handled the case is expected to take the stand when the inquiry resumes after lunch on Monday.