Piechart in R, borders too pointy on the inside

I'm making a piechart using ggplot2 and it looks fine in RStudio:

data <- data.frame(
  continent=c("Europe", "N. America", "S. America", "Asia", "Africa", "Australia"),
  value=c(80, 30, 20, 110, 40, 5)
)

library(ggplot2)
ggplot(data, aes(x="", y=value, fill=continent)) +
  geom_bar(stat="identity", width=1, color="black")+
  coord_polar("y") +
  theme_void() 
ggsave("piechart.png")

However, when I open the saved picture, you can see that the center has an unwanted spike from the green segment:

I feel this looks rather bad. Can I remove it somehow? Maybe change the line thickness so this is not as pronounced?

Edit

Setting the linejoin to 'bevel' helps w/o fiddling around with inner radius as in previous approach:

library(ggplot2)
ggplot(data, aes(x="", y=value, fill=continent)) +
  geom_bar(stat="identity", width=1, color="black",
           linejoin = 'bevel'
           )+
  coord_polar("y") +
  theme_void() 

You could use coord_radial instead of coord_polar, prevent axis expansion and set a minute inner radius:

    ggplot(data, aes(x="", y=value, fill=continent)) +
      geom_bar(stat="identity", width=1, color="black")+
      coord_radial('y', expand = FALSE, inner.radius = 0.01) +
      theme_void()