Patent ID: 7820511

Claim:
A method comprising: positioning a first mask on a layer of n-type semiconductor material, wherein the layer of n-type semiconductor layer is on a first layer of p-type semiconductor material and the first layer of p-type semiconductor material is on a substrate; selectively etching the layer of n-type semiconductor material through openings in the first mask to form an etched region and a raised region having a sidewall adjacent the etched region; removing the first mask; epitaxially growing a second layer of p-type semiconductor material on the etched and raised regions of the layer of n-type semiconductor material; positioning a second mask on the second layer of p-type semiconductor material which masks a portion of the second layer of p-type semiconductor material over the etched region and a portion of the second layer of p-type semiconductor material over the raised region; selectively etching through the second layer of p-type semiconductor material through openings in the second mask to form at least one raised p-type feature on the etched region and at least one raised p-type feature on the raised region and to selectively expose portions of the underlying layer of n-type semiconductor material adjacent and between the raised p-type features; selectively implanting n-type dopants in the exposed underlying n-type semiconductor material to form n-type implanted regions in the layer of n-type semiconductor material; removing the second mask; forming ohmic contacts on the raised p-type features and on the implanted regions in the layer of n-type semiconductor material; wherein the method optionally comprises the step of positioning a third mask on an exposed portion of the layer of n-type semiconductor material adjacent the raised p-type feature on the raised region opposite the etched region before selectively implanting n-type dopants and after selectively etching through the second layer of p-type semiconductor material.