Self-adjusting formation of a lateral confinement potential in Si/SiGe heterostructures with compensatingpnlayers

✍ Scribed by U. Wieser; S. Skaberna; U. Kunze

• Book ID: 102616107
• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 74 KB
• Volume: 23
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1006/spmi.1996.0347

✦ Synopsis

We have developed a new concept to create a lateral confinement potential in a twodimensional electron gas at the interface of a Si/SiGe heterostructure. The method is based on the compensation of the n-type doping layer by an additional p-type layer in a structure similar to a modulation-doped field-effect transistor. A numerical calculation shows that an initially depleted quantum well at zero temperature can be populated by reducing the top-layer thickness. A lateral quantum well is created below a graded step preferentially etched into the p-type layer. Beneath an etched V groove a lateral confinement is obtained with level separation in excess of 8 meV. Similar confinement is achieved in a δ-doped structure with an etch-stop controlled shallow groove.