A California mother has been sentenced to life in prison in the microwave oven death of her one-month-old daughter.

Ka Yang, 34, was sentenced Friday by a Sacramento County Superior Court judge who imposed the life sentence.

She was convicted of first-degree murder and assault for putting Mirabelle Thao-Lo in the microwave for up to five minutes inside of their Sacramento home on March 17, 2011.

Ka Yang (left), 34, was convicted of first-degree murder of Mirabelle Thao-Lo (right) and was sentenced to life in prison Friday

Prosecutors say the child had fatal thermal injuries and suffered burns on 60 percent of her body.

Dr Gregory Reiber said during a hearing in 2012 that the most serious burn appeared to be a radiation burn that penetrated the baby's internal organs and 'cooked through' to her stomach and small intestine.

He said the infant would have suffered from severe pain throughout the exposure.

At the time of her arrest, Kang was married and worked for a local architectural firm

Investigators found the infant's pacifier in the microwave at their home.

Jurors rejected the mother's argument that she had been in the middle of an epileptic seizure when she placed the infant in the microwave.

She has a history of seizures, but paramedics say she wasn't disoriented when they arrived.

Yang first told investigators and family members that she had been holding the baby when she lost consciousness while working at the computer.

She claimed that she awoke to find the infant injured next to a space heater.

However, once detectives pointed out inconsistencies in her story, the mother acknowledged that she lied and said she might have a split personality, the affidavit said.

Prosecutors alleged during her trial that Yang put the baby in the microwave because she was being irritable and fussy and holding her back from work.

Yang has three other children who are in the care of other family members.