National Semiconductor Corporation

Craig Richard Printy

Jamal Ramdani

Thanas Budri

Andre Paul Labonte

Steven J Adler

Janial Ramdani

A base structure for high performance Silicon Germanium:Carbon (SiGe:C) based heterojunction bipolar transistors (HBTs) with phosphorus atomic layer doping (ALD) is disclosed. The ALD process subjects the base substrate to nitrogen gas (in ambient temperature approximately equal to 500 degrees Celsius) and provides an additional SiGe:C spacer layer. During the ALD process, the percent concentrations of Germanium (Ge) and carbon (C) are substantially matched and phosphorus is a preferred dopant. The improved SiGe:C HBT is less sensitive to process temperature and exposure times, and exhibits lower dopant segregation and sharper base profiles.

High performance SiGe:C HBT with phosphorous atomic layer doping

A system and method is disclosed that terminates an etch process of a semiconductor crystal material at a precisely located depth. The semiconductor crystal is made of a first material and has a buried layer of a second material that is stoichiometrically different than the first material. The buried layer is located at a depth in the first material at which it is desired to terminate the etch process. During the etch process an optical emission spectrum of the first material is monitored. The intensity of the spectrum decreases when the etch process reaches the second material of the buried layer. The etch process is terminated when the decrease in spectrum intensity is detected.

System and method for controlling an etch process for a single crystal having a buried layer

A base structure for high performance Silicon Germanium:Carbon (SiGe:C) based heterojunction bipolar transistors (HBTs) with phosophorus atomic layer doping (ALD) is disclosed. The ALD process subjects the base substrate to nitrogen gas (in ambient temperature approximately equal to 500 degrees Celsius) and provides an additional SiGe:C spacer layer. During the ALD process, the percent concentrations of Germanium (Ge) and carbon (C) are substantially matched and phosphorus is a preferred dopant. The improved SiGe:C HBT is less sensitive to process temperature and exposure times, and exhibits lower dopant segregation and sharper base profiles.

One or more trenches can be formed around a first portion of a semiconductor substrate, and an insulating layer can be formed under the first portion of the semiconductor substrate. The one or more trenches and the insulating layer electrically isolate the first portion of the substrate from a second portion of the substrate. The insulating layer can be formed by forming a buried layer in the substrate, such as a silicon germanium layer in a silicon substrate. One or more first trenches through the substrate to the buried layer can be formed, and open spaces can be formed in the buried layer (such as by using an etch selective to silicon germanium over silicon). The one or more first trenches and the open spaces can optionally be filled with insulative material(s). One or more second trenches can be formed and filled to isolate the first portion of the substrate.

Semiconductor device having localized insulated block in bulk substrate and related method

A system and method is disclosed for manufacturing a bipolar junction transistor that comprises an emitter/base layer that is formed by a single deposition process. In one advantageous embodiment of the invention the emitter/base layer comprises an emitter layer that comprises an epitaxially grown mono-silicon emitter. The epitaxially grown mono-silicon emitter significantly reduces the electrical resistivity of the emitter. A non-dopant impurity such as germanium is added to the base layer to endpoint a dry plasma etch process that is applied to etch the emitter/base layer.

System and method for providing a single deposition emitter/base in a bipolar junction transistor

A system and method is disclosed for measuring a germanium concentration in a semiconductor wafer for manufacturing control of BiCMOS films. Germanium is deposited over a silicon substrate layer to form a silicon germanium film. Then a rapid thermal oxidation (RTO) procedure is performed to create a layer of thermal oxide over the silicon germanium film. The thickness of the layer of thermal oxide is measured in real time using an interferometer, an ellipsometer, or a spectroscopic ellipsometer. The measured thickness of the layer of thermal oxide is correlated to a germanium concentration of the silicon germanium film using an approximately linear correlation. The correlation enables a value of the germanium concentration in the silicon germanium film to be provided in real time.

System and method for measuring germanium concentration for manufacturing control of BiCMOS films

A base structure for high performance Silicon Germanium (SiGe) based heterojunction bipolar transistors (HBTs) with arsenic atomic layer doping (ALD) is disclosed. The ALD process subjects the base substrate to nitrogen gas or hydrogen gas (in ambient temperature approximately equal to 500 degrees Celsius) and provides an additional SiGe spacer layer. The surface of the final silicon cap layer is preferably etched to remove most of the arsenic. The resulting SiGe HBT with an arsenic ALD layer is less sensitive to process temperature and exposure times, and exhibits lower dopant segregation and sharper base profiles.

Growing community of inventors

Buxton, ME, United States of America

Craig Richard Printy